Method of viral chemoprophylaxis

ABSTRACT

It has been found that compounds having a stereochemically unencumbered access to a nitrogen-nitrogen bond have antiviral activity in extremely low dose ranges. Hydrazine, hydrazine derivatives and related compounds have been found to be active in protecting animals against disease caused by both DNA and RNA type viruses at doses of about 250 picograms to 250 micrograms per kilograms of host body weight.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a division of application Ser. No. 808,989 filed Mar. 20, 1969 and now abandoned.

BACKGROUND OF THE INVENTION

This invention relates to the chemoprophylaxis of disease caused by DNA and RNA viruses. More particularly it relates to a method of treating a virus-infected host with a class of chemical compounds at extremely low dosages in the order of about 250 picograms (10.sup.⁻¹² grams; pg) to 250 micrograms (10.sup.⁻⁶ grams; μg) per kilogram of host body weight. The difference between a picogram and a milligram is the same as the difference between one and one billion.

The compounds which are active in the practice of the present invention are those having a stereochemically unencumbered access to a nitrogen-nitrogen bond. The compounds within the purview of the invention are exemplified by those having the following formula: ##STR1## where R¹, R², R³ and R⁴ are selected from the class consisting of hydrogen, lower alkyl, aryl, heterocyclic aryl, COR⁵, CSR⁵, CONHR⁵, SO₂ R⁵ where R⁵ is lower alkyl, aryl, heterocyclic aryl, amino, lower alkoxy and adamantyl, with the proviso that R¹ and R² or R³ and R⁴ are different where R¹ or R³ is COR⁵, CSR⁵, CONHR⁵ or SO₂ R⁵. R¹ and R² or R³ and R⁴ or R¹ and R³ when taken together may be selected from the class consisting of substituted alkylidene and substituted azo. R³ and R⁴ taken together may be substituted alkylidene. R² and R⁴ may be a valence bond between the two nitrogens. As used herein the terms lower alkyl, lower alkoxy and the like define groups having 1 to about 6 carbons.

One of the problems in the field of virology has been the absence of predictability in chemoprophylaxis. Indeed, there had existed a belief among some authorities that chemoprophylaxis would not be successful in the treatment of virus infections. Up to the present time there has been no predictability with regard to the antiviral effect of particular compounds with the exception of certain compounds known to induce interferon. A compound may not be active while its homolog or a substituent is quite active. An indicated activity is frequently not reproducible with the same compound in the same dosage.

In the entire field of virology, only three compounds have been made commercially available that have antiviral effects in humans and all of these have been effective against a limited group of viruses. One of them is a compound for the treatment of kerotitis due to Herpes simplex virus. Another is a compound effective against particular strains of Influenza, and the third is a compound effective in the chemoprophylaxis of smallpox and some of the complications of vaccination.

The exact requirements for a successful antiviral compound have not been determined. Besides the chemical nature of the compound, other factors that may be involved are solubility, permeability, particle size and the like. It has been suggested that a successful antiviral agent may not attack a virus directly but rather may stimulate factors of host resistance. An effective chemoprophylactic compound is one which would have effect against a broad spectrum of virus-induced diseases, and would be effective in oral administration. Ideally, the chemoprophylactic nature of the compound should be identifiable with a particular portion of its chemical molecule and be modifiable by substituents added to the basic molecule portion. Also the therapeutic index should preferably be large, over about 100. The therapeutic index is the ratio of an acute toxic dose to an effective dose in a given host. No compound is known up to the present time which meets the ideal.

DISCUSSION

The compounds of the present invention were discovered in an antiviral screening program that was designed, among other things, to detect augmentation of host resistance. Hundreds of compounds were tested, and in the thousands of tests over this period, there was not another single instance in which a previously untested compound showed protection of more than 3 animals out of 10 at the survival level. With the compounds of the present invention from 3 to 6 survivors were observed.

Four reference compounds known to have antiviral activity have been used for comparative purposes. These are statolon, pyran copolymer, amantadine and methisazone. All of these compounds have been found to be below the ideal activity. Statolon, an interferon inducer, showed a high degree of protection against many viral infections of animals, but it is totally inactive on oral administration. Pyran copolymer, also an interferon inducer, was active only against Mengo virus infection, the most sensitive virus to interferon, and its activity was so weak that negative results were obtained with other viruses. Methisazone was active against pox virus infections of mice, but its activity is limited specifically to pox viruses, and a large dose of compound is necessary. Amantadine and related compounds have been tested. In 18 tests of amantadine on Ann Arbor Influenza virus, the most sensitive virus to amantadine, survivors were seen only on 5 occasions. In the other 13 tests protection was either not evident or was only at the increased geometric mean survival time level. In 41 tests with Influenza virus PR 8, there was only one single instance of a statistically significant number of survivors (3), and 11 instances of increased geometric mean survival time indicated by the computer. Amantadine was inactive against all of the other viruses in the test system.

The most active of the compounds of this invention are active against all of the types of Influenza against which they have been tested. On a weight basis, the compounds of this invention are a great deal more active on Influenza than the amantadines. Intrinsically, comparing the maximum protective response to the optimal dose under optimal conditions the compounds of the present invention are far better than amantadine against Ann Arbor Influenza viruses. In only one single experiment out of about 30 experiments, amantadine had a larger number of survivors than the compounds of this invention. With other compounds reported to have chemoprophylactic activity, the dose range was greatly in excess of the dose ranges found effective in the present invention.

Without wishing to be bound by a theory of operation it is believed that because of the unusual nature of the activity of the compounds of this invention, their broad spectrum, and inactivity in tissue culture, that the action of the compounds is on the host rather than on the host-virus relationship. It is believed that the activity is not the induction of interferon for it shows no activity in tissue culture as interferon does. They are weakly active on Mengo Virus infections of mice, the most sensitive strain to interferon, and no known interferon inducer is active orally, whereas the compounds of this invention are most effective when administered orally.

What is believed to be the most closely related prior art is described below. A literature search on antiviral activity of hydrazine, semicarbazide and thiosemicarbazide developed the following publications. No publication was found that reported activity of the compounds of the present invention at the very low dose levels that have not been found to be effective. There is no known prior art describing chemoprophylactic activity against a broad spectrum of viruses by orally administered compounds.

1. "In Vitro Antiviral Activity of Hydrazine Sulfate". B. Loddo, et al. Experientia 20: 326 (1964). In this paper it is reported that hydrazine sulfate is active in preventing polio and Vaccinia virus multiplication in vitro as determined by cytopathic effect in human amnion cells (Mascoli's line), and antiviral activity was reported at concentrations of from 8 to 66 micrograms per milliliter (μg/ml). This is an insensitive test influenced by numerous factors, pH, and the like, in which the growth of the virus is measured in culture medium in the presence of the compound.

In the present study of hydrazine sulfate, the more sensitive and satisfactory plaque reduction technique was used, and it was found that at the reported concentrations hydrazine was toxic to the cells. At concentrations of from 10 to 100 milligrams per milliliter (mg/ml), toxic effects on the cells were clearly evident on microscopic observation, and below the level of toxicity, no antiviral activity was demonstrated. It is well known in virology that cells injured due to toxic substances will not support the growth of viruses. It is believed that Loddo et al reported the toxic effects of hydrazine sulfate on cells as being antiviral and that their claim of antiviral activity at the concentrations used is an erroneous interpretation of their data. It has been found that hydrazine was more toxic than most of its derivatives which exhibit no cytotoxicity at levels from 50 to 100 mg/ml.

2. "Inhibitory Activity of Benzoyl Hydrazides and Hydrazine on the Growth of Influenza Virus in Chick Embryo Lung Tissue Culture". W. D. Kundin, et al. Experientia 20: 438-9 (1964). The authors report on the activity of hydrazines and some derivatives in preventing the growth of Influenza virus on embryonic chick lung tissue. The toxicity of the compounds on the tissue cultures used was established and was found to range from 0.016 to 2 mg/ml. The maximum concentration of drug inhibitory to the virus was found to range from 0.002 to 0.25 mg/ml; therefore, the therapeutic index was 8. As mentioned in relation to the Loddo et al reference above, cells under toxic influences do not grow viruses. In this paper the inhibitory effect reported as due to the compounds appears to be a misinterpretation of the experiment and may actually be due to the toxic activity of the compound on the cells.

3. "Potential Antiviral Thiourea Derivatives". Ng. Ph. Buu-Hoi, et al. J. Chem. Soc. 1956, 2160-5. In this paper the authors show that several compounds containing a nitrogen-nitrogen bond have antiviral activity and report on the chemical synthesis of several compounds containing this linkage. The details of the antiviral tests are not given in the above paper, but are reported in Compt. rend., 1954, 238, 2583 (Buu-Hoi, et al). All activity is reported at relatively high doses, and they did not test at the low dose levels found essential for a broad spectrum of activity.

4. There are many papers in the literature by Dr. John Bauer and his associates on the Effects of Methisazone on pox viruses. The activity of methisazone is altered greatly by very slight changes on the side chains of the semicarbazide. Relatively high doses are necessary for protective effects. There is no reported activity against any viruses other than pox viruses. There are no reports in the literature on the activity of methisazone or related compounds against either RNA or DNA viruses at low concentration.

5. In a paper by Cifuentes-Bernal et al "Treatment of Infectious Canine Hepatitis with a Monoamine Oxidase Inhibiting Drug", Toxicology and Applied Pharmacology 12, 508-517 (1968), a study was made on the treatment of infectious canine hepatitis with a monoamine oxidase inhibiting drug, nialamide. The rationale was to determine if monoamine oxidase inhibiting drugs that have been reported to protect against hepatic damage might reduce the hepatic injury in cases of infectious canine hepatitis and thus protect the animals. At doses of 50 milligrams per kilogram (mg/kg) of body weight, protection was found when 15 of 16 treated animals survived and 5 of 6 control animals died. In the paper no mention is made of treatment with very low doses. The authors describe the action of nialamide as the inhibition of monoamine oxidase.

6. Methylgloxal-bis-guanylhydrazone (methyl-GAG) is known to reduce haemagglutination (HA) titres of Influenza A PR8 virus multiplying in chorioallantoic membrane (CAM) cultures and in embryonated eggs. The treatment ranged from 0.125 to 1000 mg. methyl-GAG per ml. Ninety percent inhibition was obtained at the lower limit while the upper limit was toxic. C. Kuchler et al. Acta virol. 12:441-445, 1968.

OBJECTS OF THE INVENTION

It is an object of the present invention to provide antiviral dose forms which are effective in oral administration.

It is another object of this invention to provide chemical compounds which are effective against viral diseases which have predictable and reproducible behavior in known doses.

It is another object of the present invention to identify compounds having antiviral activity at a high therapeutic index.

It is a further object of the present invention to provide a method of antagonizing viral diseases by chemoprophylaxis.

It is another object of this invention to identify a class of compounds having a readily recognizable characteristic structure in which all members are chemopropylactic compounds.

It is another object of the present invention to provide a method of treating viral infections in lower animals, such as laboratory experimental animals, household pets, farm animals, and show or exhibition animals, including white mice and the like.

It is another object of the present invention to provide a method of recognizing and selecting compounds which are of practical application in veterinary medicine.

SUMMARY OF THE INVENTION

It has been found that certain compounds exert a pronounced chemoprophylactic effect on viral infections of animals. The compounds found effective to date in the practice of this invention are hydrazine, hydrazine sulfate; semicarbazide, hydrochloride; thiosemicarbazide; 2-butanone, thiosemicarbazone; aminoguanidine, bicarbonate; isoniazid; hydralazine; methisazone; [(2,6-dichlorobenzylidine)amino]guanidine acetate; 3-pentanone, thiosemicarbazone; 2-pentanone, thiosemicarbazone; acetone, thiosemicarbazone; 1-(sec-butylideneamino)guanidine, nitrate; acetoacetic acid, ethyl ester, thiosemicarbazone; 1,2-dimethylhydrazine, dihydrochloride; 1,1-dimethylhydrazine; methylhydrazine; 2-indanone, thiosemicarbazone; cyclopentanone, 3-thio-4-o-tolylsemicarbazone.

It has been found that compounds which afford unencumbered access to a nitrogen-nitrogen bond are active. The compounds are active against both ribonucleic acid (RNA) type viruses and desoxyribonucleic acid (DNA) type viruses. All of the above named compounds have been shown to be active on at least one viral infection, and as a class of compounds they have been shown to be effective in protecting mice against Herpes and Vaccinia viruses (DNA viruses), as well as strains A, A₁ and B of Influenza virus, and Mengo and Columbia SK Polio viruses (RNA viruses). Chemoprophylaxis has been demonstrated in three animal species. Chick embryos have been protected against Herpes virus; the course of Vaccinia infection of the rabbit skin has been modified, and protection is afforded against all of the above-named viruses in the mouse. The compounds show no activity in tissue culture. They have the unique property of protecting animals at remarkably low concentrations and surprisingly are inactive at higher doses. Under optimum conditions the preferred dose appears to lie between 250 nanograms (10.sup.⁻⁹ grams; ng) and 250 micrograms per kilogram, but activity has been demonstrated with total doses as low as 250 picograms (pg) per kilogram of host body weight. The acute toxicity of the more toxic compounds is about 25 milligrams per kilogram, and therefore the effective dose is less than one-one-thousandth of the acute toxic dose.

Optimal efficacy is dependent upon a dose-dose schedule relationship, appearing to be more active when a dose is administered at 48 hour intervals, with prolonged pre-treatment. Administration of the drugs at forty-eight hour intervals for up to 6 days prior to virus challenge appears to increase the overall efficacy of the procedure, increasing the percentage of the animals that survive the virus challenge. In such a method of treatment activity is demonstrated over a wide range of doses, several ten-fold dilutions.

All of the compounds tested are as effective, or more effective on oral administration as they are on parenteral administration. Often, under optimal conditions of administration, from 30 to 60 percent (%) of the treated animals survive the virus challenge--an overwhelming lethal infection in which 100% of the control animals are almost invariably killed. There is no dose response curve in the usual sense. A protective effect is observed which is more pronounced with the proper dose-dose schedule relationship.

DETAILED DESCRIPTION

It has been found that the compounds of the present invention are active prophylactically against many viral diseases of animals. It has been found that, of the DNA viruses, mice are protected against Herpes simplex virus. The activity of the compounds of the present invention on Herpes also can be demonstrated in eggs where a protective effect upon the intact embryo is exerted. Vaccinia infections of the mouse tail have been shown to be modified by the compounds of the present invention as is Vaccinia infection of the rabbit skin. Neurovaccinia in the mouse brain (an overwhelming infection) has been shown statistically to be influenced. Among the RNA viruses, Influenza A (PR 8), Influenza A₁ (Ann Arbor), Influenza B (Mass.) and Influenza B (Maryland) are influenced by the compounds of the present invention. Mengo virus infection in mice is moderately sensitive to the compounds that have been tested. Activity has been found against Columbia SK polio in mice.

In a preliminary study, the protective effect of the compounds of this invention was evident using statistical techniques and rarely was there protection at the survival level. As methodology was perfected it was found that the best results were obtained on oral administration of the drugs and when they were administered at 48 hour intervals with one to three or more doses prior to infection. With these conditions 3, 4, or even 5 survivors of 10 animals in a group are found. This degree of protection is highly significant because these are overwhelming infections in which 100% of the controls almost invariably die. However, highly lethal infections must be used to provide laboratory guides for the treatment of diseases of higher animals which are quite mild by comparison, particularly upper respiratory diseases, where only a minute fraction of the total cells of the body are involved.

It also has become evident that the protective effect of the compounds of this invention is most dramatic when the virus challenge is low and, as mentioned above, in many of the diseases of higher animals for which prophylactic approaches are feasible, the virus challenge also is very low. Better results are obtained where the virus challenge is equal to the challenge that kills fifty percent of the hosts (LD₅₀) than where the challenge is three times LD₅₀.

It has long been recognized that to be widely used, a chemoprophylactic antiviral agent should have certain properties. It should be active on oral administration. It should be active at a minute fraction of its toxic dose and have no unfavorable side effects. It should protect against a wide range of different and unrelated viral agents, and it should be effective when administered over a long period of time, with no development of insensitivity to the substance or resistance in the virus.

Not all compounds with a nitrogen-nitrogen bond have equal activity, and there may be a difference in susceptibility of different viruses to different compounds.

Tests of thiosemicarbazone on Vaccinia in the rabbit skin have been reasonably consistent with highly significant diminution of pox formation at narrow dose levels, 0.25 or 2.5 micrograms per kilogram of host body weight (μg/kg). Results with 2-butanone, thiosemicarbazone have been variable, and the reasons for this have not yet been determined.

In order more clearly to disclose the nature of the present invention, specific examples of the practice of the invention are hereinafter given. It should be understood, however, that this is done solely by way of example and is intended neither to delineate the scope of the invention nor limit the ambit of the appended claims.

In the tables the virus used in the test is indicated at the top together with the host, the dose schedule and the route of administration. In each test, not otherwise described, there were 10 animals at each dose level, and 20 controls. The tables are summaries of the observations showing, for each dose level, the number of animals surviving at the end of the experiment, the number surviving for 1 day or longer after 100% of the controls were dead, and the number of animals surviving after approximately 80 to 90% of the controls were dead. As 20 control animals were used and 10 test animals, in order to make a direct comparison, the number of surviving control animals has been divided by two, thus if three control animals survive at 8 days it would be recorded as 11/2 animals. To control the influence of stress, each time a treated group was administered a dose of drug, the control animals were administered a dose of saline or distilled water by the same route.

As used herein, the abbreviation "NS" means "not significant". The symbol "-" before a number in a dose schedule indicates the number of hours prior to infection that the dose was administered. The symbol "+" before a number in a dose schedule indicates the number of hours after infection that the dose was administered.

EXAMPLE 1

The following example illustrates the effect of test compounds against Herpes virus in mice. The results are shown in tables 1-9 and 50.

It was found that Herpes virus was quite sensitive to the action of the compounds of this invention and the Herpes virus test was used to determine those compounds that had antiviral activity. As the work progressed it became increasingly clear that small doses gave the best results, and later it was found that drug administered at 48 hour intervals gave even better results.

Early in the studies it was found that more consistent and uniform results could be obtained when the drug was given orally rather than parenterally, and for this reason almost all of the experiments were conducted using oral administration.

In the earlier stages significance was at the increased geometric mean survival time level, and it was rare that there was statistical significance at the survival level. As more optimal conditions were found it was not uncommon, although not uniform, to find 3, 4, or 5 of the treated animals surviving. (Tables 1,2,3,4). Earlier in this work it was found that the antiviral activity consisted of protecting an occasional animal so that it survived throughout the experiment, resulting in the computer recording the observation as statistically significant at the geometric mean survival time level, and in these instances usually the remaining treated animals died at almost exactly the same rate as the controls. (Table 50). When more optimal conditions were determined and used many of the treated animals survived after most of the control animals died. (Table 5).

When it was found that surprisingly low doses of drug were most active and when these were used at 48 hour intervals, activity at significant levels was observed over a wide range of dose levels up to several log dilutions. Under non-optimal conditions more variable results were observed and activity often was found at a single dose level. (Table 4). This is typical of many experiments done under less than ideal conditions.

                                      TABLE 1                                      __________________________________________________________________________     Virus: Herpes Virus                                                            Dose Schedule: -50, -25 pre-infection; +17, +65, +114 post-infection           Route of Administration: Oral                                                  Host: Mouse                                                                    __________________________________________________________________________                        Total Dose Administered to the                                                 Animal in Micrograms                                        Compound           5  .5 .05                                                                               .005                                                                              .0005                                                                              Control                                     __________________________________________________________________________     Thiosemi-                                                                            Survivors    1  3  3  4  3     0                                         carbazide                                                                            No. animals surviving                                                          when 100% of controls                                                          are dead     2  3  3  5  3     0                                               No. animals surviving                                                          after 7 days 4  4  2  6  6     21/2                                      __________________________________________________________________________     semicarba-                                                                           Survivors    1  0  1  5  1     0                                         zide                                                                                 No. animals surviving                                                          when 100% of controls                                                          are dead     2  1  2  5  1     0                                               No. animals surviving                                                          after 7 days 7  4  5  8  5     21/2                                      __________________________________________________________________________     hydrazine                                                                            Survivors    2  1  0  4  3     0                                               No. animals surviving                                                          when 100% of controls                                                          are dead     0  1  1  0  0     0                                               No. animals surviving                                                          after 7 days 7  6  5  6  5     21/2                                      __________________________________________________________________________

                                      TABLE 2                                      __________________________________________________________________________     Virus: Herpes Virus                                                            Dose Schedule: -50, -25 pre-infection; +17, +65, +114 post-infection           Route of Administration: Oral                                                  Host: Mouse                                                                    __________________________________________________________________________                        Total Dose Administered to the                                                 Animal in Micrograms                                        Compound           5  .5 .05                                                                               .005                                                                              .0005                                                                              Control                                     __________________________________________________________________________     Thiosemi-                                                                            Survivors    1  3  3 4   3     0                                         carbazide                                                                            No. animals surviving                                                          when 100% controls                                                             are dead     1  3  3 5   3     0                                               No. animals surviving                                                          after 9 days 2  3  4 5   5     1/2                                       __________________________________________________________________________     semicar-                                                                             Survivors    1  0  1 5   1     0                                         bazide,                                                                        hydro-                                                                               No. animals surviving                                                    chloride                                                                             when 100% controls                                                             are dead     2  1  2 0   0     0                                               No. animals surviving                                                          after 9 days 4  1  3 7   4     1/2                                       __________________________________________________________________________

                                      TABLE 3                                      __________________________________________________________________________     Virus: Herpes Virus                                                            Dose Schedule: -96, -48 pre-infection; +1, +49, +97 post-infection.            Route of Administration: Oral.                                                 Host: Mouse                                                                    __________________________________________________________________________                        Total Dose Administered to the                                                 Animal in Micrograms                                        Compound           5  .5 .05                                                                               .005                                                                              .0005                                                                              Control                                     __________________________________________________________________________     Thiosemi-                                                                            Survivors    0  1  1  2  0   1/2                                         carbazide                                                                            No. animals surviving                                                          when 19/20 controls                                                            are dead     0  1  1  2  2   1/2                                               No. animals surviving                                                          after 8 days 0  3  4  3  1   1                                           __________________________________________________________________________     semicarba-                                                                           Survivors    3  5  4  2  1   1/2                                         zide, hydro-                                                                   chloride                                                                             No. animals surviving                                                          when 19/20 controls                                                            are dead     4  5  4  2  1   1/2                                               No. animals surviving                                                          after 8 days 5  5  4  3  1   1                                           __________________________________________________________________________

                                      TABLE 4                                      __________________________________________________________________________     Virus: Herpes Virus                                                            Dose Schedule: -48, -25 pre-infection; ±17, +65, +114 post-infection.       Route of Administration: Oral.                                                 Host: Mouse                                                                    __________________________________________________________________________                         Total Dose Administered to the                                                 Animal in Micrograms                                       Compound            .05                                                                               .005                                                                              .0005                                                                              .00005                                                                             .000005                                                                             Control                                 __________________________________________________________________________     Thiosemi-                                                                             Survivors    0  0  0   3   0      11/2                                  carbazide                                                                             No. animals surviving                                                          when 17/20 controls                                                            are dead     0  2  0   3   0      11/2                                         No. animals surviving                                                          after 9 days 1  5  2   6   2      3                                     __________________________________________________________________________     Isoniazid                                                                             Survivors    1  1  0   2   3      11/2                                         No. animals surviving                                                          when 17/20 controls                                                            are dead     1  2  0   3   3      11/2                                         No. animals surviving                                                          after 9 days 2  3  4   5   3      3                                     __________________________________________________________________________     2-Butanone,                                                                           Survivors    0  2  4   3   0      11/2                                  thiosemi-                                                                      carbazone                                                                             No. animals surviving                                                          when 17/20 controls                                                            are dead     0  3  5   4   0      11/2                                         No. animals surviving                                                          after 9 days 3  4  6   8   1      3                                     __________________________________________________________________________

                                      TABLE 5                                      __________________________________________________________________________     Virus: Herpes Virus                                                            Dose Schedule: -52, -22 pre-infection; +19, +65, +114 post-infection.          -Route of Administration: Oral.                                                Host: Mouse                                                                    __________________________________________________________________________                     Total Dose Administered to the                                                 Animal in Micrograms                                           Compound        .05                                                                               .005                                                                              .0005                                                                              .00005                                                                             .000005                                                                             .0000005                                                                            Control                                __________________________________________________________________________     Hydralazine                                                                           Survivors                                                                               0  2  2   0   0    1    0                                             No. Animals                                                                    surviving when                                                                 100% controls                                                                  are dead 0  2  2   0   0    1    0                                             No. animals                                                                    surviving after                                                                8 days   1  3  2   2   4    1    1                                      __________________________________________________________________________     Methisa-                                                                              Survivors                                                                               0  0  1   3   1    1    0                                      zone                                                                                  No. animals                                                                    surviving when                                                                 100% controls                                                                  are dead 0  0  1   4   1    1    0                                             No. animals                                                                    surviving after                                                                8 days   2  3  3   4   3    4    1                                      __________________________________________________________________________

                                      TABLE 6                                      __________________________________________________________________________     Virus: Herpes Virus                                                            Dose Schedule: -48 pre-infection; +4, +52, +96, +120 post-infection.           Route of Administration: Oral.                                                 Host: Mouse                                                                    __________________________________________________________________________                         Total Dose Administered to the                                                 Animal in Micrograms                                       Compound            .005                                                                              .0005                                                                              .00005                                                                             .000005                                                                             Control                                    __________________________________________________________________________     semicar-                                                                              Survivors    0  1   1   0      0                                        bazide                                                                                No. animals surviving                                                          when 100% of controls                                                          are dead     0  1   2   1      0                                               No. animals surviving                                                          after 9 days 1  1   3   1      11/2                                     __________________________________________________________________________

                                      TABLE 7                                      __________________________________________________________________________     Virus: Herpes Virus                                                            Dose Schedule: -120, -72, -24 pre-infection; +24, +72 post-infection           Route of Administration: Oral                                                  Host: Mouse                                                                    __________________________________________________________________________                         Total Dose Administered to the                                                 Animal in Micrograms                                       Compound            .005                                                                              .0005                                                                              .00005                                                                             .000005                                                                             Control                                    __________________________________________________________________________     Isoniazid                                                                             Survivors    0  1   0   0    0                                                 No. animals surviving                                                          when 100% of controls                                                          are dead     1  1   0   0    0                                                 No. animals surviving                                                          after 6 days 2  3   0   1    1                                          __________________________________________________________________________     Hydrala-                                                                              Survivors    0  0   1   0    0                                          zine                                                                                  No. animals surviving                                                          after 100% of controls                                                         are dead     0  1   1   0    0                                                 No. animals surviving                                                          after 6 days 1  1   2   0    1                                          __________________________________________________________________________     Methisa-                                                                              Survivors    1  0   0   0    0                                          zone                                                                                  No. animals surviving                                                          when 100% of controls                                                          are dead     0  0   0   0    0                                                 No. animals surviving                                                          after 6 days 0  0   0   1    1                                          __________________________________________________________________________

                                      TABLE 8                                      __________________________________________________________________________     Virus: Herpes Virus                                                            Dose Schedule: -96, -48 pre-infection; +1, +49, +97 post-infection.            Route of Administration: Oral                                                  Host: Mouse                                                                    __________________________________________________________________________                        Total Dose Administered to the                                                 Animal in Micrograms                                        Compound           5  .5 .05                                                                               .005                                                                              .0005                                                                              Control                                     __________________________________________________________________________     hydrazine                                                                            Survivors    2  0  2  3  3   1/2                                               No. animals surviving                                                          when 19/20 of controls                                                         are dead     2  1  2  3  5   1/2                                               No. animals surviving                                                          after 8 days 2  1  3  6  6   1                                           __________________________________________________________________________

                                      TABLE 9                                      __________________________________________________________________________     Virus: Herpes Virus                                                            Dose Schedule: -120, -75, -24 pre-infection; ±24, +72 post-infection        Route of Administration: Oral.                                                 Host: Mouse                                                                    __________________________________________________________________________                     Total Dose Administered to the                                                 Animal in Micrograms                                           Compound        .05                                                                               .005                                                                              .0005                                                                              .00005                                                                             .000005                                                                             .0000005                                                                            Control                                __________________________________________________________________________     Isoniazid                                                                             Survivors                                                                               1  1  0   1   2    1      0                                           No. animals                                                                    surviving when                                                                 100% controls                                                                  are dead 1  1  0   1   2    1      0                                           No. animals                                                                    surviving af-                                                                  ter 8 days                                                                              4  1  1   1   2    4      31/2                                 __________________________________________________________________________     Hydralazine                                                                           Survivors                                                                               2  1  1   1   1    1      0                                           No. animals                                                                    surviving when                                                                 100% controls                                                                  are dead 2  1  2   3   1    1      0                                           No. animals                                                                    surviving af-                                                                  ter 8 days                                                                              3  2  3   4   2    1      31/2                                 __________________________________________________________________________     Methisa-                                                                              Survivors                                                                               0  1  0   2   1    0      0                                    zone                                                                                  No. animals                                                                    surviving when                                                                 100% controls                                                                  are dead 0  1  0   3   1    0      0                                           No. animals                                                                    surviving af-                                                                  ter 8 days                                                                              1  3  1   4   3    3      31/2                                 __________________________________________________________________________

EXAMPLE 2

The following example illustrates the effect of test compounds of this invention against Herpes virus in eggs. The results are shown in Table 10.

Chicken eggs were injected with a single dose of several hydrazine drugs administered in the allantoic cavity 24 hours prior to infection with Herpes virus in yolk sac. (Table 10). All of the 24 controls were dead at the end of the 4th day, and a small percentage of the embryos survived longer than the controls, a few being alive at the 22nd day. Nine of those that were alive were helped to hatch and live baby chicks were walking around the incubator. It was impressive to see living chicks surviving on the 22nd day a virus challenge that killed all of the controls on the 4th day. This is unequivocal evidence that the compounds are active on Herpes virus in eggs.

                                      TABLE 10                                     __________________________________________________________________________     Herpes Virus in Eggs.                                                          Virus: Herpes                                                                  Dose Schedule: Single Dose 24 hours pre-infection. -12 eggs used in each       test, each egg weighing 50 to 60 grams.                                        All controls died on the 4th day.                                              __________________________________________________________________________     Total              Total      No. Living                                       Dose in    Deaths on Days                                                                         Deaths-                                                                             No. Dying                                                                            Longer Than                                                                           No.                                       Compound                                                                             μg                                                                               1 2 3 4 4th Day                                                                             5-22 Day                                                                             Controls                                                                              Hatched                                   __________________________________________________________________________     Control                                                                              0    4 8 10                                                                               2 24/24                                                       __________________________________________________________________________     Semicar-                                                                             00005                                                                               4 3 4   11   1     1                                                bazide                                                                               .0005                                                                               2 2 6 1 11   0     1      1                                               .005 2 2 3   7    2     4      1                                               .05  1 4 6   11   0     1                                                      .5   2 2 5   9    2     2                                                      2    2 2 3 3 10   0     0                                                      20   3 1 5 2 11   0     1                                                __________________________________________________________________________     Total                         10     2                                         2-Butanone                                                                           .00005                                                                              2 4 5   11   0     1      1                                         thiosemi-                                                                            .0005                                                                               1 5 3 1 10   0     2      1                                         carbazone                                                                            .005 2 4 2 3 11   0     1                                                      .05  2 6 3   11   1     1                                                      .5   1 3 6 2 12   0     0                                                      2    1 5 3   9    2     3      1                                               20     5 1 2 8    1     4      2                                         __________________________________________________________________________     Total                         12     5                                         Thiosemi-                                                                            .00005                                                                              2 5 2 1 10   0     1                                                carbazide                                                                            .0005                                                                               2 3 2 3 10   0     1      not                                             .005 4 3 3   10   1     2      helped                                          .05    3 5   9    0     1      to                                              .5   3 4 2 2 11   0     1      hatch                                           2    3 1 5 3 12   0     0                                                      20   1 4 6 1 12   0     0                                                __________________________________________________________________________     Total                         7                                                Hydrazine                                                                            .00005                                                                              2 2 5   9    0     1                                                      .0005                                                                               2 6 4   12   0     0                                                      .005   7 4   11   0     0                                                      .05  2 5 3   10   0     0                                                      .5   2 2 5 1 10   0     0                                                      2    3 4 1 1 9    0     1      1                                               20   3 2 4 2 11   0     1      1                                         __________________________________________________________________________     Total                         3      2                                         __________________________________________________________________________

EXAMPLE 3

The following example illustrates the effect of the test compounds against Influenza Ann Arbor virus. The results are shown in Tables 11-30. The effect of the hydrazine compounds on the Ann Arbor strain of Influenza virus was studied in mice. It is evident with this virus that optimal results were obtained on oral administration. As illustrated in Table 11, when semicarbazide was administered subcutaneously there was a total of only three survivors at 4 dose levels, whereas under oral administration under similar conditions, there were ten survivors. Tables 12 and 13 present interesting results because they show quite clearly the upper and lower limits of activity, there being no activity at 500 μg and none at 0.05 μg or below, with significant survivors in the three dose levels in between. Under more optimal conditions of administration it appears that a larger dose of drug is needed to give maximum protective effect. This protective effect is demonstrable over several log dilutions of drug, whereas without optimal conditions activity was only demonstrable over a narrow dose range. The data suggest that with different compounds different dilutions of drug may yield optimal results. Table 14 shows that aminoguanidine at 30 μg, the maximum dose level used, is the most active. This indicates that with some of the other compounds of this invention a larger dose may be necessary to give the most effective results.

At times there are unexplained and apparently uncontrolled variations between very similar experiments. A comparison of Tables 12, 13 and 15 may illustrate this. Hydrazine was tested in two experiments on different dates but using identical procedures and techniques. There are slight differences between the two that illustrate one type of uncontrolled variation that is encountered. The same virus suspension was used on different dates in these experiments. If Table 15 is compared with these, the only difference being that here the oral route of administration was used, it is evident that much less significant activity was demonstrated. This experiment was done with a new lot of virus and the control animals died much more quickly--there being a more severe virus challenge. Similar observations have been made with Influenza Virus, PR 8, in which with several virus challenges few survivors are evident. This may indicate that the protective effect of the compounds of this invention is most pronounced when the virus challenge is not overwhelming. The observations on Vaccinia in the mouse tail and Vaccinia in the rabbit skin both support this concept.

                                      TABLE 11                                     __________________________________________________________________________     Virus: Influenza, Ann Arbor                                                    Dose Schedule: -24 pre-infection; +24, +72, +96 post-infection                 Route of Administration: Subcutaneous and oral                                 Host: Mouse                                                                    __________________________________________________________________________                         Total Dose Administered to the                                                 Animal in Micrograms.                                      Compound            .5 .05                                                                               .005                                                                              .0005                                                                              Control                                       __________________________________________________________________________     Route of Administration: Subcutaneous                                          semicarba-                                                                            Survivors    1  0  1  1     0                                           zide                                                                                  No. animals surviving                                                          when 100% of controls                                                          are dead     1  0  1  2     0                                                  No. animals surviving                                                          after 9 days 1  0  2  4     11/2                                        __________________________________________________________________________     Route of Administration: Oral.                                                 semicarb-                                                                             Survivors    3  3  1  3   0                                             azide                                                                                 No. animals surviving                                                          when 100% of controls                                                          are dead     3  3  1  3   0                                                    No. animals surviving                                                          after 9 days 3  3  1  3   11/2                                          __________________________________________________________________________

                                      TABLE 12                                     __________________________________________________________________________     Virus: Influenza, Ann Arbor, Virus                                             Dose Schedule: -24 pre-infection, +24, +72 post-infection                      Route of Administration: Subcutaneous.                                         Host: Mouse                                                                    __________________________________________________________________________                   Total Dose Administered to the                                                 Animal in Micrograms                                             Compound      500                                                                               50 5  .5 .05                                                                               .005                                                                              .0005                                                                              .00005                                                                             Control                                __________________________________________________________________________     hydrazine,                                                                           Survivors                                                                              0  1  3  3  0  0  0   0      0                                   hydrate                                                                              No. animals                                                                    surviving                                                                      when 100%                                                                      controls                                                                       are dead                                                                               0  3  3  3  0  1  2   0      0                                         No. animals                                                                    surviving                                                                      after 7 days                                                                           6  7  6  7  4  3  5   1      11/2                                __________________________________________________________________________

                                      TABLE 13                                     __________________________________________________________________________     Virus: Influenza, Ann Arbor, Virus                                             Dose Schedule: -24 pre-infection; +24, +72 post-infection.                     Route of Administration: Subcutaneous.                                         Host: Mouse                                                                    __________________________________________________________________________                   Total Dose Administered to the                                                 Animal in Micrograms                                             Compound      500                                                                               50 5  .5 .05                                                                               .005                                                                              .0005                                                                              .00005                                                                             Control                                __________________________________________________________________________     hydrazine,                                                                           Survivors                                                                              0  0  2  0  1  2  2   0   0                                      hydrate                                                                              No. animals                                                                    surviving                                                                      when 100%                                                                      controls                                                                       are dead                                                                               2  2  5  1  3  2  5   0   0                                            No. animals                                                                    surviving                                                                      after 5 days                                                                           3  4  6  5  6  4  7   1   4                                      __________________________________________________________________________

                                      TABLE 14                                     __________________________________________________________________________     Virus: Influenza, Ann Arbor, Virus                                             Dose Schedule: -24 pre-infection; +24, +72 post-infection                      Route of Administration: Oral and subcutaneous                                 Host: Mouse                                                                    __________________________________________________________________________                         Total Dose Administered to the                                                 Animal in Micrograms                                       Compound            30 3  .3 .03                                                                               .003                                                                              .0003                                                                              Control                                 __________________________________________________________________________     Route of Administration: Oral                                                  amino- Survivors    5  3  4  2  1  1   0                                       guanidine                                                                             No. animals surviving                                                          when 100% of controls                                                          are dead     6  5  4  3  1  1   0                                              No. animals surviving                                                          after 7 days 8  8  7  7  7  6   31/2                                    __________________________________________________________________________     Route of Administration: Subcutaneous.                                         amino- Survivors    2  2  1  1  0  5   0                                       quanidine                                                                             No. animals surviving                                                          when 100% of controls                                                          are dead        2  2  2  3  6   0                                              No. animals surviving                                                          after 7 days    6  7  7  8  8   31/2                                    __________________________________________________________________________

                                      TABLE 15                                     __________________________________________________________________________     Virus Influenza, Ann Arbor                                                     Dose Schedule: -24,pre-infection; +24, +72 post-infection.                     Route of Administration: Oral.                                                 Host: Mouse                                                                    __________________________________________________________________________                    Total Dose Administered to the                                                 Animal in Micrograms                                            Compound       500                                                                               50 5  .5 .05                                                                               .005                                                                              .0005                                                                              .00005                                                                             Control                               __________________________________________________________________________     Methisa-                                                                             Survivors   0  0  0  0  0  0   0     0                                   zone                                                                                 No. animals sur-                                                               viving when 100%                                                               controls are                                                                   dead        1  2  2  0  0  3   1     0                                         No. animals sur-                                                               viving after 5                                                                 days        3  4  6  4  5  5   6     21/2                                __________________________________________________________________________     hydrazine                                                                            Survivors                                                                               0  0  0  0  1  0  0   0     0                                   hydrate                                                                              No. animals sur-                                                               viving when 100%                                                               controls are                                                                   dead     3  1  2  2  2  1  4   4     0                                         No. animals sur-                                                               viving after 5                                                                 days     5  4  4  6  3  3  6   6     21/2                                __________________________________________________________________________

                                      TABLE 16                                     __________________________________________________________________________     Virus: Influenza, Ann Arbor                                                    Dose Schedule: -120, -72, -24 pre-infection; +24, +72, +120                    post-infection.                                                                Route of Administration: Oral.                                                 Host: Mouse                                                                    __________________________________________________________________________                        Total Dose Administered to the                                                 Animal in Micrograms.                                       Compound           .5  .05 .005 Control                                        __________________________________________________________________________     semicarba-                                                                           Survivors    0   0   0      0                                            zide                                                                                 No. animals surviving                                                          when 100% of controls                                                           are dead    0   0   0      0                                                  No. animals surviving                                                          after 8 days 0   0   1      21/2                                         __________________________________________________________________________     Thiosemi-                                                                            Survivors    0   1   1      0                                            carbazide                                                                            No. animals surviving                                                          when 100% of controls                                                          are dead     3   1   1      0                                                  No. animals surviving                                                          after 8 days 3   4   1      21/2                                         __________________________________________________________________________     Isoniazid                                                                            Survivors    1   1   2      0                                                  No. animals surviving                                                          when 100% of controls                                                          are dead     1   1   2      0                                                  No. animals surviving                                                          after 8 days 1   2   2      21/2                                         __________________________________________________________________________

                  TABLE 17                                                         ______________________________________                                         Virus: Influenza, Ann Arbor                                                    Dose Schedule:                                                                 -140, -96, -48 pre-infection; 0, +48, +96 post-infection.                      Route of Administration: Oral.                                                 Host: Mouse                                                                                     Total Dose Administered to the                                Com-             Animal in Micrograms.                                         pound            .5     .05    .005 Control                                    ______________________________________                                         semi- Survivors      1      1    1    0                                              No. animals surviving                                                    carba-                                                                               when 100% of controls                                                          are dead       1      1    1    0                                        zide  No. animals surviving                                                          after 8 days   3      2    4     21/2                                    thio- Survivors      0      2    1    0                                        semi- No. animals surviving                                                          when 100% of controls                                                    carba-                                                                               are dead       2      3    1    0                                              No. animals surviving                                                    zide  after 8 days   6      5    2     31/2                                    Iso-  Survivors      2      2    2    0                                              No. animals surviving                                                    nia-  when 100% of controls                                                          are dead       2      2    2    0                                        zid   No. animals surviving                                                          after 8 days   6      5    5     21/2                                    ______________________________________                                    

                  TABLE 18                                                         ______________________________________                                         VIRUS: Influenza, Ann Arbor                                                    Dose Schedule: -24 pre-infection; +24, +72 post-infection.                     Route of Administration: Oral                                                  Host: Mouse                                                                    Compound Total Dose Administered to the Animal                                 [(2,6-dichlor-                                                                 obenzylidine)-                                                                 amino]guani-                                                                            3     300    30  3   300  30  3   300  30  Con-                       dine acetate                                                                            mg    μg  μg                                                                              μg                                                                              ng   ng  ng  pg   pg  trol                       ______________________________________                                         Survivors                                                                               *     0      0   0   0    0   0   1    0   0                          No. animals                                                                    surviving                                                                      when, 100%                                                                              *     0      2   1   0    0   3   1    2   0                          of controls                                                                    are dead                                                                       No. animals                                                                    surviving                                                                               *     1      3   2   1    1   4   2    4   2                          after 6 days                                                                   ______________________________________                                          * Toxic                                                                  

                  TABLE 19                                                         ______________________________________                                         VIRUS: Influenza, Ann Arbor                                                    Dose Schedule: -24; +24, +72                                                   Route of Administration: Oral                                                  Host: Mouse                                                                    Compound      Total Dose Administered to the Animal                            3-pentanone, thiosemi-                                                                       150    120    90  60  24  18  12  Con-                           carbazone     μg  μg  μg                                                                              μg                                                                              μg                                                                              μg                                                                              μg                                                                              trol                           ______________________________________                                         Survivors     1      1      0   0   0   1   0   0                              No. animals surviving                                                          when, 100% of con-                                                                           1      1      3   0   0   1   0   0                              trols are dead                                                                 No. animals surviving                                                          after 7 days  2      1      3   1   0   1   1   1/2                            ______________________________________                                    

                  TABLE 20                                                         ______________________________________                                         VIRUS: Influenza, Ann Arbor                                                    Host: Mouse                                                                    Dose Schedule: -24 pre-infection; +24, +72 post-infection.                     Route of Administration: Oral.                                                 Compound   Total Dose Administered to the Animal                               3-pentanone,                                                                   thiosemi-  300    30    3   300  30  3   300  30  Con-                         carbazone  μg  μg μg                                                                              ng   ng  ng  pg   pg  trol                         ______________________________________                                         Survivors  0      0     1   0    0   0   0    0   0                            No. animals                                                                    surviving                                                                      when 100% of                                                                              3      3     3   1    0   0   1    0   0                            animals are                                                                    dead                                                                           No. animals                                                                    surviving  4      7     6   3    0   3   1    2   1                            after 6 days                                                                   ______________________________________                                    

                  TABLE 21                                                         ______________________________________                                         VIRUS: Influenza, Ann Arbor                                                    Host: Mouse                                                                    Dose Schedule: -24; +24, +72                                                   Route of Administration: Oral.                                                 Compound Total Dose Administered to the Animal                                 2-pentanone,                                                                   thiosemicar-                                                                            2.25   1.5   750  225  150  75  22.5 15  Con-                         bazone   μg  μg ng   ng   ng   ng  ng   ng  trol                         ______________________________________                                         Survivors                                                                               1      0     0    0    0    0   0    0   0                            No. animals                                                                    surviving                                                                      when, 100%                                                                              1      0     1    1    0    0   0    1   0                            of controls                                                                    are dead                                                                       No. animals                                                                    surviving                                                                               1      2     2    3    0    1   0    3   1/2                          after 7 days                                                                   ______________________________________                                    

                  TABLE 22                                                         ______________________________________                                         VIRUS: Influenza, Ann Arbor                                                    Host: Mouse                                                                    Dose Schedule: -24 pre-infection; +24, +72 post-infection.                     Route of Administration: Oral.                                                 Compound   Total Dose Administered to the Animal                               2-pentanone,                                                                   thiosemi-  300    30    3   300  30  3   300  30  Con-                         carbazone  μg  μg μg                                                                              ng   ng  ng  pg   pg  trol                         ______________________________________                                         Survivors  0      1     0   0    0   0   0    0   0                            No. animals                                                                    surviving                                                                      when, 100% of                                                                             0      1     1   1    1   1   0    2   0                            controls                                                                       are dead                                                                       No. animals                                                                    surviving  0      1     1   1    2   2   2    2   1                            after 6 days                                                                   ______________________________________                                    

                  TABLE 23                                                         ______________________________________                                         VIRUS: Influenza, Ann Arbor                                                    Host: Mouse                                                                    Dose Schedule: -24 pre-infection; +24, +72 post-infection.                     Route of Administration: Oral.                                                 Compound   Total Dose Administered to the Animal                               acetone,                                                                       thiosemi-  300    30    3   300  30  3   300  30  Con-                         carbazone  μg  μg μg                                                                              ng   ng  ng  pg   pg  trol                         ______________________________________                                         Survivors  0      0     0   0    0   0   0    1   0                            No. animals                                                                    surviving                                                                      when, 100% of                                                                             0      1     4   0    2   1   0    1   0                            controls                                                                       are dead                                                                       No. animals                                                                    surviving  3      2     5   3    2   2   2    3   1                            after 6 days                                                                   ______________________________________                                    

                  TABLE 24                                                         ______________________________________                                         VIRUS: Influenza, Ann Arbor                                                    Host: Mouse                                                                    Dose Schedule: -24; +24, +72                                                   Route of Administration: Oral                                                                   Total Dose Administered to the                                Compound         Animal.                                                       1-(sec-butylideneamino)-                                                                        300   30    3   300  30  3   Con-                             guanidine, nitrate                                                                              μg μg μg                                                                              ng   ng  ng  trol                             ______________________________________                                         Survivors        0     2     0   2    0   0   0                                No. animals surviving                                                          when 100% of controls                                                                           0     2     0   3    0   0   0                                are dead                                                                       No. animals surviving                                                          after 7 days     0     2     0   3    1   0   1/2                              ______________________________________                                    

                  TABLE 25                                                         ______________________________________                                         VIRUS: Influenza, Ann Arbor                                                    Host: Mouse                                                                    Dose Schedule: -24; +24, +48                                                   Route of Administration: Oral                                                  Compound Total Dose Administered to the Animal                                 acetoacetic                                                                    acid, ethyl                                                                    ester,                                                                         thiosemi-                                                                               3     300    30  3   300  30  3   300  30  Con-                       carbazone                                                                               mg    μg  μg                                                                              μg                                                                              ng   ng  ng  pg   pg  trol                       ______________________________________                                         Survivors                                                                               0     0      0   0   0    0   0   0    0   0                          No. animals                                                                    surviving                                                                      when, 100%                                                                              1     3      3   2   2    3   2   2    5   0                          of controls                                                                    are dead                                                                       No. animals                                                                    surviving                                                                               5     7      8   6   4    5   5   4    8   3                          after 5 days                                                                   ______________________________________                                    

                  TABLE 26                                                         ______________________________________                                         VIRUS: Influenza, Ann Arbor                                                    Host: Mouse                                                                    Dose Schedule: -24; +24, +72                                                   Route of Administration: Oral                                                  Compound Total Dose Administered to the Animal                                 1,2-dimethyl-                                                                  hydrazine, di-                                                                          3     300    30  3   300  30  3   300  30  Con-                       hydrochloride                                                                           mg    μg  μg                                                                              μg                                                                              ng   ng  ng  pg   pg  trol                       ______________________________________                                         Survivors                                                                               0     0      0   0   0    1   0   0    1   0                          No. animals                                                                    surviving                                                                      when 100%                                                                               0     2      2   1   2    1   2   1    4   0                          of controls                                                                    are dead                                                                       No. animals                                                                    surviving                                                                               3     6      4   3   5    3   3   2    6    21/2                      after 6 days                                                                   ______________________________________                                    

                                      TABLE 27                                     __________________________________________________________________________     VIRUS: Influenza, Ann Arbor                                                    Host: Mouse                                                                    Dose Schedule: -24; +24, +72                                                   Route of Administration: Oral                                                  Compound   Total Dose Administered to the Animal                                          3 300                                                                               30                                                                               3 300                                                                               30  3 300                                                                               30                                                                               Con-                                         1,1-dimethylhydrazine                                                                     mg                                                                               μg                                                                             μg                                                                            μg                                                                            ng ng                                                                               ♀                                                                         ng                                                                               pg pg                                                                               trol                                         __________________________________________________________________________     Survivors  0 0  1 0 0  0   1 0  0 0                                            No. animals surviving                                                          when,100% of controls                                                                     1 1  1 0 2  1   3 0  3 0                                            are dead                                                                       No. animals surviving                                                          after 6 days                                                                              2 3  1 2 3  2   3 3  5 21/2                                         __________________________________________________________________________

                  TABLE 28                                                         ______________________________________                                         VIRUS: Influenza, Ann Arbor                                                    Host: Mouse                                                                    Dose Schedule: -24; +24, +72                                                   Route of Administration: Oral                                                  Compound Total Dose Administered to the Animal                                 Methyl-  3     300    30  3   300  30  3   300  30  Con-                       hydrazine                                                                               mg    μg  μg                                                                              μg                                                                              ng   ng  ng  pg   pg  trol                       ______________________________________                                         Survivors                                                                               *     0      1   0   0    1   1   0    1   0                          No. animals                                                                    surviving                                                                      when, 100%                                                                              *     0      2   0   0    1   2   1    2   0                          of controls                                                                    are dead                                                                       No. animals                                                                    surviving                                                                               *     1      3   3   1    4   3   3    2   21/2                       after 6 days                                                                   ______________________________________                                          * Toxic                                                                  

                  TABLE 29                                                         ______________________________________                                         VIRUS: Influenza, Ann Arbor                                                    Host: Mouse                                                                    Dose Schedule: -24, +24, +48                                                   Route of Administration: Oral                                                  Compound Total Dose Administered to the Animal                                 2-indanone,                                         3                          thiosemi-                                                                               3     300    30  3   300  30  3   300  30  Con-                       carbazone                                                                               mg    μg  μg                                                                              μg                                                                              ng   ng  ng  pg   pg  trol                       ______________________________________                                         Survivors                                                                               *     0      0   1   1    0   0   0    1   0                          No. animals                                                                    surviving                                                                      when, 100%                                                                              *     2      5   2   1    2   1   2    4   0                          of controls                                                                    are dead                                                                       No. animals                                                                    surviving                                                                               *     6      8   8   8    9   5   8    8   3                          after 5 days                                                                   ______________________________________                                    

                  TABLE 30                                                         ______________________________________                                         VIRUS: Influenza, Ann Arbor                                                    Host: Mouse                                                                    Dose Schedule: -24, +24, +48                                                   Route of Administration: Oral                                                  Compound Total Dose Administered to the Animal                                 cyclopenta-                                                                    none, 3-thio-                                                                  4-O-tolylsemi-                                                                          3     300    30  3   300  30  3   300  30  Con-                       carbazone                                                                               mg    μg  μg                                                                              μg                                                                              ng   ng  ng  pg   pg  trol                       ______________________________________                                         Survivors                                                                               0     0      0   0   0    1   0   0    0   0                          No. animals                                                                    surviving                                                                      when, 100%                                                                              3     4      1   2   1    5   3   5    3   0                          of controls                                                                    are dead                                                                       No. animals                                                                    surviving                                                                               8     9      5   6   6    9   9   9    6   3                          after 5 days                                                                   ______________________________________                                    

EXAMPLE 4

The following example illustrates the effect of the compounds of this invention on Influenza PR 8 virus. The results are shown in Tables 31-38.

The effect of the hydrazine derivatives on Influenza PR 8 virus was studied in mice. This strain of Influenza seems somewhat more resistant to all of the drugs than the Ann Arbor strain. Nevertheless in Table 31 with no pretreatment, the effect is seen in which only animals that survive are affected, all other animals dying at the same time as the controls, whereas Tables 32 and 33 show that under more optimal conditions with pre-treatment, more of the treated animals lived longer than the controls.

Thiosemicarbazone was administered to animals infected with Influenza virus in their drinking water. (Table 34). It is striking that a significant number of survivors were observed when the drug was administered for only a period of 48 hours; 24 hours pre- and 24 hours post-infection. Also at a single dose level there were significant survivors when the animals were allowed access to the drug for only a 24 hour period post-infection.

                  TABLE 31                                                         ______________________________________                                         Virus: Influenza, PR 8                                                         Dose Schedule: No pre-infection; +30, +72 post-infection.                      Route of Administration: Intravenous.                                          Host: Mouse                                                                                     Total Dose Administered                                                        to the Animal in Micrograms.                                  Compound           20     2      .2   Control                                  ______________________________________                                         2-butanone,                                                                            Survivors      3      3    2    1                                              No. animals surviving                                                  thiosemi-                                                                              when 18/20 of controls                                                         are dead       3      3    2    1                                      carbazone                                                                              No. animals surviving                                                          after 9 days   3      3    2    1                                      ______________________________________                                    

                                      TABLE 32                                     __________________________________________________________________________     Virus: Influenza, PR 8                                                         Dose Schedule: -24 pre-infection; +3, +24, +72 post-infection.                 Route of Administration: Oral.                                                 Host: Mouse                                                                                    Total Dose Administered to the                                                 Animal in Micrograms.                                          Compound        .5                                                                               .05                                                                              .005                                                                              .0005                                                                              .00005                                                                             .000005                                                                             Control                                    __________________________________________________________________________     hydrazine,                                                                           Survivors 1 1 1  2   4   2    0                                          hydrate                                                                              No. animals survi-                                                             ving when 18/20 of                                                             controls are dead                                                                        1 1 1  3   4   2    1                                                No. animals survi-                                                             ving after 8 days                                                                        2 3 2  3   5   4     21/2                                      semicarba-                                                                           Survivors 1 4 0  0   0   0    0                                          zide                                                                                 No. animals survi-                                                             ving when 18/20 of                                                             controls are dead                                                                        3 4 0  0   0   2    1                                                No. animals survi-                                                             ving after 8 days                                                                        3 4 0  1   0   2     21/2                                      __________________________________________________________________________

                                      TABLE 33                                     __________________________________________________________________________     Virus: Influenza PR 8 Virus                                                    Dose Schedule: -49 pre-infection: +4, +48, +96 post-infection.                 Route of Administration: Oral                                                  Host: Mouse                                                                                       Total Dose Administered to the                                                 Animal in Micrograms                                        Compound           .005                                                                              .0005                                                                              .00005                                                                             .000005                                                                             Control                                     __________________________________________________________________________     2-butanone,                                                                           Survivors   2  1   4   1    0                                           thiosemi-                                                                      carbazone                                                                             No. animals surviving                                                          after 100% of controls                                                         are dead    2  1   4   2    0                                                  No. animals surviving                                                          after 7 days                                                                               2  3   8   4     11/2                                       hydrazine,                                                                            Survivors   2  1   0   2    0                                           hydrate                                                                               No. animals surviving                                                          when 100% of controls                                                          are dead    2  1   0   4    0                                                  No. animals surviving                                                          after 7 days                                                                               5  2   0   4     11/2                                       semicar-                                                                              Survivors   0  0   2   0    0                                           bazide                                                                                No. animals surviving                                                          when 100% of controls                                                          are dead    0  0   0   0    0                                                  No. animals surviving                                                          after 7 days                                                                               1  1   3   1     11/2                                       __________________________________________________________________________

                  TABLE 34                                                         ______________________________________                                         Virus: Influenza PR 8                                                           Drug Dissolved in Drinking Water                                              Animals allowed to drink ad lib for 24 hours pre- and 24                       hours post-infection.                                                          Host: Mouse                                                                                     Concentration of Compound                                                      in Water in Mg/ml                                             Compound               10     5   0.5  .05 Control                             ______________________________________                                         2-butanone,                                                                            Survivors      2      3   1    3   0                                   thiosemi-                                                                      carbazone                                                                              No. animals surviving                                                          when 100% of controls                                                          are dead       2      3   2    3   0                                           No. animals surviving                                                          after 8 days   4      3   2    4   1                                   ______________________________________                                         Same as above except animals were allowed access to the drug                   for 24 hours post-infection only.                                              ______________________________________                                         2-butanone,                                                                            Survivors           0      3   0                                       thiosemi-                                                                      carbazone                                                                              No. animals surviving                                                          when 100% of controls                                                          are dead            0      3   0                                               No. animals surviving                                                          after 8 days        1      3   1                                       ______________________________________                                    

                                      TABLE 35                                     __________________________________________________________________________     Virus: Influenza, PR 8                                                         Dose Schedule: -144, -96, -48 pre-infection; +4, +48, +96                      post infection.                                                                Route of Administration: Oral.                                                 Host: Mouse                                                                    Total Dose Administered to the                                                 Animal in Micrograms                                                           __________________________________________________________________________     Compound           .005                                                                               .0005                                                                               .00005                                                                              .000005                                                                             Control                                  __________________________________________________________________________     2-butanone,                                                                           Survivors    0   1     4    1   1/2                                     thiosemi-                                                                      carbazone                                                                             No. animals surviving                                                          when 19/20 of controls                                                         are dead     0   1     4    2   1/2                                            No. animals surviving                                                          after 8 days 0   3     4    3   1                                       __________________________________________________________________________

                                      TABLE 36                                     __________________________________________________________________________     Virus: Influenza, PR 8 Virus                                                   Dose Schedule: -21 pre-infection; +3, +24, +72 post-infection.                 Route of Administration: Oral.                                                 Host: Mouse                                                                                  Total Dose Administered to the                                                 Animal in Micrograms.                                            Compound      5 .5                                                                               .05 .005                                                                               .0005                                                                               .00005                                                                              .000005                                                                              .0000005                                                                             Control                        __________________________________________________________________________     Isoniazid                                                                            Survivors                                                                              2 1 1    1   0    0     0     0    0                                   No. animals                                                                    surviving when                                                                 100% controls                                                                  are dead                                                                               2 1 0    1   0    0     1     0    0                                   No. animals                                                                    surviving                                                                      after 7 days                                                                           5 2 2    1   0    0     2     1    1                             __________________________________________________________________________

                                      TABLE 37                                     __________________________________________________________________________     Virus: Influenza PR 8 Virus                                                    Host: Mouse                                                                    Dose Schedule: -24 pre-infection; +4, +24, +72 post-infection.                 Route of Administration: Oral and subcutaneous                                                    Total Dose Administered to the                                                 Animals in Micrograms.                                      Compound           .005                                                                               .0005                                                                               .00005                                                                              .000005                                                                              Control                                 __________________________________________________________________________     Route of Administration: Oral                                                  2-butanone,                                                                          Survivors    1   1    2    0     0                                       thiosemi-                                                                      carbazone                                                                            No. animals surviving                                                          when 100% of controls                                                          are dead     1   1    3    3     0                                             No. animals surviving                                                          after 6 days 2   2    5    6     21/2                                    __________________________________________________________________________     Route of Administration: Subcutaneous                                          2-butanone,                                                                          Survivors    0   1    0    0     0                                       thiosemi-                                                                      carbazone                                                                            No. animals surviving                                                          when 100% of controls                                                          are dead     1   1    0    1     0                                             No. animals surviving                                                          after 6 days 3   1    3    2     21/2                                    __________________________________________________________________________

                                      TABLE 38                                     __________________________________________________________________________     Virus: Influenza, PR 8                                                         Host: Mouse                                                                    Dose Schedule: -24 pre-infection; +24 post-infection.                          Route of Administration: Oral.                                                                    Total Dose Administered to the                                                 Animal in Micrograms.                                       __________________________________________________________________________     Compound           50 5 .5                                                                               .05                                                                               .005                                                                               .0005                                                                               Control                                  __________________________________________________________________________     hydrazine,                                                                           Survivors    0  0 1 0   3   1     0                                      hydrate                                                                              No. animals surviving                                                          when 100% of controls                                                          are dead     0  0 1 0   3   1     0                                            No. animals surviving                                                          after 10 days                                                                               1  1 1 0   3   1     1                                      __________________________________________________________________________

EXAMPLE 5

The following example illustrates the effect of the test compounds on Influenza B Massachusetts virus. The results are shown in Tables 39 and 40.

The activity of four compounds on Influenza B Mass. was tested in mice. It is evident from Tables 39 and 40 that the test compounds have activity at the geometric mean survival time level.

Geometric mean survival time is the nth route of the n-fold product of the individual survival times of each of the animals where n is the number of animals tested. The foregoing may be expressed by the formula: ##EQU1##

                                      TABLE 39                                     __________________________________________________________________________     Virus: Influenza B-Mass. Virus                                                 Dose Schedule: -120, -72, -24 pre-infection; +24, +72 post-infection.          Route of Administration: Oral.                                                 Host: Mouse                                                                                   Total Dose Administered to the                                                 Animal in Micrograms                                            __________________________________________________________________________     Compound       .5                                                                               .05                                                                               .005                                                                               .0005                                                                               .00005                                                                              .000005                                                                              Control                                __________________________________________________________________________     2-butanone,                                                                           Survivors                                                                              1 0   0   0    2     2    0                                     thiosemi-                                                                      carbazone                                                                             No. animals                                                                    surviving when                                                                 100% controls                                                                  are dead                                                                               4 2   0   1    3     3    0                                            No. animals                                                                    surviving af-                                                                  ter 5 days                                                                             5 4   4   7    8     6    2                                     Isoniazid                                                                             Survivors                                                                              0 0   0   0    0     0    0                                            No. animals                                                                    surviving when                                                                 100% controls                                                                  are dead                                                                               0 1   1   2    1     0    0                                            No. animals                                                                    surviving af-                                                                  ter 5 days                                                                             3 3   5   3    2     3    2                                     semicar-                                                                              Survivors                                                                              0 0   0   0    0     0    0                                     bazide                                                                                No. animals                                                                    surviving when                                                                 100% controls                                                                  are dead                                                                               1 1   3   1    0     0    0                                            No. animals                                                                    surviving af-                                                                  ter 5 days                                                                             4 6   6   3    3     3    2                                     __________________________________________________________________________

                                      TABLE 40                                     __________________________________________________________________________     VIRUS: Influenza - B-Mass.                                                     Host: Mouse                                                                    Dose Schedule: -24; +24, +72, +100                                             Route of Administration: Oral                                                                Total Dose Administered to the                                   Compound      Animal                                                           __________________________________________________________________________     aminoguanidine, bicarbo-                                                       nate          4μg                                                                             400ng                                                                               40ng                                                                               4ng                                                                               400pg                                                                               40pg                                                                               Control                                 __________________________________________________________________________     Survivors     1    1    1   0  2    0    0                                     No. animals surviving                                                          when, 100% of controls                                                                       1    1    2   1  2    0    0                                     are dead                                                                       No. animals surviving                                                          after 7 days  3    3    7   4  4    2    1                                     __________________________________________________________________________

EXAMPLE 6

The following example illustrates the effect of the test compounds on Influenza B Maryland virus. The results are shown in Table 41. The table shows that 1-methylindole-2,3-dione,3-thiosemicarbazone (methisazone) is active against Influenza B Maryland virus.

                                      TABLE 41                                     __________________________________________________________________________     VIRUS: Influenza, B Maryland                                                   Host: Mouse                                                                    Dose Schedule: -144, -96, -48 pre-infection; +3, +48, +96                      post-infection.                                                                Route of Administration: Oral.                                                                   Total Dose Administered to the                               Compound          Animal.                                                      __________________________________________________________________________     1-methylindole-2,3-dione,3-                                                    thiosemicarbazone (Methisazone)                                                                  6μg                                                                             600 ng                                                                              60 ng                                                                               6 ng                                                                              Control                                     __________________________________________________________________________     Survivors          1    2   2    2  1                                          No. animals surviving                                                          when 18/20 of controls                                                                            4    2   4    4  1                                          are dead                                                                       No. animals surviving                                                          after 8 days       5    4   8    5  21/2                                       __________________________________________________________________________

EXAMPLE 7

The following example shows the effect of the compounds of this invention on Columba SK Polio virus in mice. The experiments were done many weeks before optimal conditions of dosage and treatment were known. There are two instances of a statistically significant geometric mean survival time for thiosemicarbazone. The compounds are unequivocally active against this virus, but its actual degree of sensitivity has not been determined. The results are shown in Table 42.

                  TABLE 42                                                         ______________________________________                                         VIRUS: Columbia SK Polio                                                       Dose Schedule: -24 pre-infection; +3, +24 post-infection.                      Route of Administration: Subcutaneous.                                         Host: Mouse                                                                                     Total Dose Administered to                                                     the Animal.                                                   ______________________________________                                         Compound           300 ng  30ng   3 ng Control                                 ______________________________________                                                 Survivors        1      0    0     0                                   2-butanone                                                                     thiosemi-                                                                              No. animals surviving                                                  carbazone                                                                              when 100% of controls                                                                           2      3    3     0                                           are dead                                                                       No. animals surviving                                                          after 5 days     6      8    7     3                                   ______________________________________                                    

EXAMPLE 8

The following example illustrates the effect of the compounds of the invention on Mengo virus in mice. The results are illustrated in Table 43. It is evident that there is a protective effect on the mouse hosts.

                                      TABLE 43                                     __________________________________________________________________________     Virus: Mengo Virus                                                             Host: Mouse                                                                    Dose Schedule: -24 pre-infection; +24, +72 post-infection.                     Route of Administration: Oral.                                                                 Total Dose Administered to the                                                 Animal in Micrograms.                                          __________________________________________________________________________     Compound        .005                                                                               .0005                                                                               .00005                                                                              .000005                                                                              .0000005                                                                             Control                              __________________________________________________________________________     Thiosemi-                                                                            Survivors  0   0     1    1     0     0                                  carbazide                                                                            No. animals survi-                                                             ving when 100% of                                                              controls are dead                                                                         0   0     2    2     1     0                                        No. animals survi-                                                             ving after 6 days                                                                         1   1     5    2     1     1                                  __________________________________________________________________________

EXAMPLE 9

The following example illustrates the effect of the compounds of the invention on Vaccinia virus. The results are shown in Table 44. The effect of the hydrazine compounds on Vaccinia virus was studied in the mouse tail. The virus was administered intravenously into the tail vein of the mouse and the degree of swelling and vessicle formation in the treated animals was compared with the controls. Table 44 shows that there is a statistically significant difference between many of the treated and the control animals. All of these animals were held for 21 days, and there was no evidence of a recurrence of lesions such as was seen in the preliminary studies on Vaccinia in rabbits. (Example 11). In earlier tests done under less optimal conditions there was evidence of recurrence of lesions on the tails at about the 14th or 15th day.

                                      TABLE 44                                     __________________________________________________________________________     Virus: Vaccinia IHD                                                            Pre-treatment administered intravenously.                                      Post-treatment administered orally.                                            Host: Mouse -                                                                  Com- Total                                                                              Statistical Significance of Tail Lesions on Days                      __________________________________________________________________________     pound                                                                               Dose                                                                               5   6   7   8   10  11  12  14  17   21                               __________________________________________________________________________     Thio-                                                                               10ng                                                                               NS  NS  NS  NS  NS  NS  <.05                                                                               <.05                                                                               <.05                                                                               <.05                              semicar-                                                                            100 NS  NS  NS  <.05                                                                               <.01                                                                               <.01                                                                               <.01                                                                               <.01                                                                               <.01                                                                               <.01                              bazide                                                                              1μg                                                                             <.01                                                                               <.01                                                                               <.01                                                                               <.01                                                                               <.01                                                                               <.01                                                                               <.01                                                                               <.01                                                                               <.01                                                                               <.01                                   10  NS  <.01                                                                               NS  NS  <.05                                                                               <.01                                                                               <.01                                                                               <.01                                                                               <.01                                                                               <.01                              2-buta-                                                                             10ng                                                                               <.05                                                                               <.01                                                                               <.05                                                                               NS  <.01                                                                               <.01                                                                               <.01                                                                               <.01                                                                               <.01                                                                               <.01                              none,                                                                               100 <.05                                                                               <.01                                                                               <.01                                                                               <.01                                                                               <.01                                                                               <.01                                                                               <.01                                                                               <.01                                                                               <.01                                                                               <.01                              thiose-                                                                             1.0μg                                                                           <.01                                                                               <.01                                                                               <.05                                                                               <.01                                                                               <.01                                                                               <.01                                                                               <.01                                                                               <.01                                                                               <.01                                                                               <.01                              micar-                                                                              10  NS  <.01                                                                               <.05                                                                               <.05                                                                               <.01                                                                               <.05                                                                               <.05                                                                               <.05                                                                               <.01                                                                               <.01                              bazone                                                                         hydra-                                                                              10ng                                                                               NS  <.01                                                                               <.05                                                                               NS  NS  <.01                                                                               <.01                                                                               <.01                                                                               <.01                                                                               <.01                              zine 100 <.05                                                                               <.01                                                                               <.01                                                                               <.05                                                                               <.01                                                                               <.01                                                                               <.01                                                                               <.01                                                                               <.01                                                                               <.01                                   1.0μg                                                                           NS  NS  NS  NS  <.01                                                                               <.01                                                                               <.01                                                                               <.01                                                                               <.01                                                                               <.01                                   10  NS  NS  NS  NS  <.05                                                                               <.01                                                                               <.01                                                                               <.01                                                                               <.01                                                                               <.01                              semicar-                                                                            10ng                                                                               NS  <.01                                                                               NS  NS  NS  <.05                                                                               <.05                                                                               NS  <.05                                                                               NS                                bazide,                                                                             100 NS  NS  <.05                                                                               NS  NS  <.05                                                                               <.05                                                                               <.05                                                                               <.01                                                                               <.01                              hydro-                                                                              1.0μg                                                                           NS  <.01                                                                               NS  <.01                                                                               <.01                                                                               <.01                                                                               <.01                                                                               <.01                                                                               <.01                                                                               <.05                              chloride                                                                            10  NS  NS  <.01                                                                               NS  <.05                                                                               <.01                                                                               <.01                                                                               <.01                                                                               <.01                                                                               <.05                              __________________________________________________________________________

EXAMPLE 10

The following example illustrates the effect of the compounds of this invention on Neurovaccinia. Several tests of the hydrazines on Neurovaccinia in mice have been carried out. In these tests the virus challenge was intracerebral and several of the compounds of this invention were administered either subcutaneously or orally. This is an overwhelming infection and very few compounds have ever been found to show any significant effect. In three instances, thiosemicarbazide, at a single dose level has shown one surviving animal, and it was found that this was computed as statistically significant at geometric mean survival time level. The results are shown in Table 45.

                                      TABLE 45                                     __________________________________________________________________________     VIRUS: Neurovaccinia                                                           Dose Schedule: -24 pre-infection; +24, +72 post-infection.                     Route of Administration: Intraperitoneal.                                      Host: Mouse                                                                                          Total Dose Administered to the                                                Animal.                                                   __________________________________________________________________________     Compound             .75 μg                                                                           .075 μg                                                                           .0075μg                                                                           Control                                  __________________________________________________________________________             Survivors      0    1     0     0                                      semicarbazide                                                                          No. animals surviving                                                  hydrochloride                                                                          when 100% of controls                                                                         1    1     0     0                                              are dead                                                                       No. animals surviving                                                          after 6 days   1    11/2  1/2   1/2                                    __________________________________________________________________________

EXAMPLE 11

The following example illustrates the effect of the compounds of this invention on Vaccinia virus. The results are shown in Table 46. A few experiments were performed studying the influence of thiosemicarbazone and thiosemicarbazide on the development of pox formation from Vaccinia virus in the scarified rabbit skin. An experiment on thiosemicarbazone showed very striking effects of the drug on the pox formation, there being dramatic reduction and even elimination of all pox formation over several dilutions. In a few instances, but not all, after another 24 hours there was some evidence of recurrence of the pox. This experiment was repeated twice, unsuccessfully. The preparations used in the test were analyzed, and it was found that the submission sample of thiosemicarbazone was contaminated with a small percentage of thiosemicarbazide. The preparations of the latter thiosemicarbazone that were injected into the rabbits in the case of the unsuccessful experiments contained, for some unexplained reason, no detectable thiosemicarbazide. Thiosemicarbazide was then tested repeatedly with highly significant and reproducible protective effects. It has not yet been determined whether it was the presence of the contaminant thiosemicarbazide in the preparations of thiosemicarbazone that gave protective effects or some other phenomena. Table 46 gives the results of three tests done consecutively on thiosemicarbazide and in each instance it was found that when the rabbit was given either 0.25 or 2.5 μg/kg there was a highly significant diminution in the vaccinia pox formation. In most instances after a second 24 hour period some recurrence of the pox was evident.

All of these experiments were carried out with the drug administered intraperitoneally, a route that is now known to be the least efficacious in the mouse. It remains to be determined whether more optimal conditions of administration will give more uniform, consistent and permanent effects on Vaccinia in the rabbit.

Vaccinia Virus in Rabbits

On three occasions identical experiments were carried out in which rabbits were injected with thiosemicarbazide, 24 hours before vaccination, vaccinated on the second day at which time a second dose of drug was given, and on the third day a third dose of drug was administered, all intraperitoneally. The results of the test were read on the 5th day. The results obtained were as follows, the figures being approximate percentage confluency of the pox on the scarified area.

                  TABLE 46                                                         ______________________________________                                                                           (Duplicate                                   μg/kg Test 1   Test 2   Test 3 Experiments)                                 ______________________________________                                         Control 1                                                                               80%      95%      80     95                                           Control 2                                                                               90%      85%      70     90                                           250      80%                                                                   25       80%      10%                                                          2.5      50%      80%      30     30                                                                      20     20                                           0.25     10%      10%      30     --                                                                      40     --                                           0.025     5%       5%      75     75                                                                      90     80                                           0.0025    2%      80%      85     75                                                                      85     60                                           0.00025           40%                                                          0.000025          25%                                                          0.0000025         85%                                                          ______________________________________                                    

A T test on these data resulted in the following findings:

    ______________________________________                                         Dose 0.025            T = 1.99;NS                                              Dose 0.25             T = 6.437;S<.01                                          Dose 2.5              T = 4.911;S<.01                                          ______________________________________                                    

At the 0.25 and the 2.5 μg/kg levels it is very highly significant, far less than 0.01. The 2.5 μg/kg dose corresponds to 50 nanograms per mouse (ng/mouse), and the 0.25 μg/kg dose corresponds to 5 ng/mouse.

EXAMPLE 12

The following example illustrates the effect of the compounds of the invention in tissue cultures. The compounds were tested against Herpes, Influenza and Vaccinia virus in tissue culture using both pre- and post-treatment of the cells, and dilutions down to 0.001 picograms. All tests were negative.

The effect of various concentrations of thiosemicarbazide and semicarbazide on Vaccinia pox formation on the chorioallantoic membrane of fertile eggs was studied. No effect on pox formation on the membrane could be observed. This is in accord with other experimentation because pox formation on membranes is actually a specialized form of tissue culture and no activity has been demonstrable in tissue culture.

Several of these compounds were tested for viricidal activity, and none was demonstrated.

EXAMPLE 13

The following example illustrates the optimal routes of administration of the compounds of this invention. The results are shown in Tables 11, 14, 34 and 47.

A test on Influenza PR 8 virus administered in drinking water was done and the results are shown in table 34. It is clearly evident that animals receiving thiosemicarbazone for 24 hours pre- and 24 hours post-infection in drinking water were significantly protected against death. Administration of drug for only 24 hours post-infection provided significant protection at a single dose level.

Table 47 shows a comparison of oral, subcutaneous and intraperitoneal administration of thiosemicarbazide against Influenza PR 8 virus. It is evident here that in this experiment intraperitoneal administration gave almost no protection, whereas oral and subcutaneous administration was effective and gave comparable results. It has been found that with the subcutaneous route of administration a larger dose of drug is required than when the oral route of administration is used.

Table 11 shows the effect of oral and subcutaneous administration of semicarbazide on Influenza, Ann Arbor virus. Again, it is clearly evident that oral administration is better with significant protection over a wide range, 10 survivors being observed over four log doses whereas under identical conditions with subcutaneous administration only 3 animals survived over a four log dose range.

Table 14 shows the results of a study of oral and subcutaneous administration of aminoguanidine on Influenza Ann Arbor infections of mice. On oral administration at a high dose, 50% of the treated animals survived, and the effect is spread over several dose ranges from 0.3 to 30 μg/dose. In this experiment, with subcutaneous administration, 50% survival was found only at one dose level, and not spread as seen above. These experiments clearly indicate that oral is the preferred route of administration.

                                      TABLE 47                                     __________________________________________________________________________     Virus: Influenza, PR 8 Virus                                                   Dose Schedule: -24 pre-infection; +3, +24 post-infection.                      Route of Administration: Oral, Subcutaneous, Intraperitoneal                   Host: Mouse                                                                                             Total Dose Administered to the                                                 Animal in Micrograms                                  Compound: Thiosemicarbazide                                                                             5 .5                                                                               .05 .005                                                                               .0005                                                                               Control                              __________________________________________________________________________     ORAL                                                                                      Survivors     1 0 1   3   2    0                                               No. animals surviving                                                          when 100% of controls                                                          are dead      1 0 1   3   2    0                                               No. animals surviving                                                          after 8 days  3 1 2   3   2    1                                    SUBCUTANEOUS                                                                              Survivors     3 2 2   0   0    0                                               No. animals surviving                                                          when 100% of controls                                                          are dead      3 2 2   1   0    0                                               No. animals surviving                                                          after 8 days  3 2 2   1   2    1                                    INTRAPERITONEAL                                                                           Survivors     0 0 0   0   1    0                                               No. animals surviving                                                          when 100% of controls                                                          are dead      0 0 0   0   2    0                                               No. animals surviving                                                          after 8 days  1 0 1   2   2    1                                    __________________________________________________________________________

EXAMPLE 14

The following example illustrates the optimal dose schedules of the compounds useful in the practice of this invention. The results are shown in Tables 11-14 and 47-50.

The early work on these compounds was done in experiments in which the drugs were administered on a dose schedule of about 24 hours. Table 47 illustrates the effects seen with such a schedule. In the table, on oral administration, the total number of treated animals surviving longer than control animals is somewhat less at all dose levels than that seen with more favorable dose schedules. It has now been found that a treatment schedule with about 48 hour intervals between doses gives somewhat better results. Such a schedule is illustrated in Tables 12-14 and 48.

A few studies have been done in which no pre-treatment was administered. Table 50 shows the results of this on Herpes virus infection, with semicarbazide, and erratic results are evident, although at one dose level 50% of the animals were protected.

Table 49 shows the results of post-infection treatment only on Herpes virus with semicarbazide. In one case treatment was initiated two hours after infection, in a second case four hours after infection, and in the third case twenty hours post-infection, all with no pre-treatment. When the first drug was administered two hours after infection from 20 to 30% of the animals survived at certain dose levels. At eight hours after infection 2 animals survived, and when treatment was delayed until after twenty hours, only an occasional animal survived. It is striking that even with a twenty hour delay of treatment after infection a protective effect is produced sufficiently great that it is demonstrable by inspection rather than by the use of statistics.

                                      TABLE 48                                     __________________________________________________________________________     Virus: Herpes Virus                                                            Dose Schedule: -24 pre-infection; +24, +72, +120 post-infection.               Route of Administration: Oral                                                  Host: Mouse                                                                                      Total Dose Administered to the                                                 Animal in Micrograms                                         Compound          .005                                                                               .0005                                                                               .00005                                                                              .000005                                                                             Control                                   __________________________________________________________________________     semicar-                                                                            Survivors    2   2    3    0    0                                         bazide                                                                              No. animals surviving                                                          when 100% of controls                                                          are dead     2   2    3    0    0                                              No. animals surviving                                                          after 9 days 3   2    3    0    11/2                                      __________________________________________________________________________

                                      TABLE 49                                     __________________________________________________________________________     Virus: Herpes Virus                                                            Host: Mouse                                                                    Route of Administration: Oral                                                                    Total Dose Administered to the                                                 Animal in Micrograms                                         compound: Semicarbazide                                                                          .005                                                                               .0005                                                                               .00005                                                                              .000005                                                                              Control                                  __________________________________________________________________________     Dose Schedule: No pre-infection;                                                                 +2, +50, +98, +146 post-infection.                           semicar-                                                                            Survivors    3   0    3    2     0                                        bazide                                                                              No. animals surviving                                                          when 100% of controls                                                          are dead     3   0    3    3     0                                             No. animals surviving                                                          after 8 days 3   0    3    4     1                                        __________________________________________________________________________     Dose Schedule: No pre-infection; +8, +56, +105, +152 post-infection.           Survivors         0   2    0    0     0                                        No. animals surviving                                                          when 100% of controls                                                          are dead          0   3    0    0     0                                        No. animals surviving                                                          after 8 days      1   2    2    1     1                                        __________________________________________________________________________     Dose Schedule: No pre-infection; +20, +29, +77, +125 post-infection            Survivors         1   1    0    1     0                                        No. animals surviving                                                          when 100% of controls                                                          are dead          1   3    1    2     0                                        No. animals surviving                                                          after 8 days      1   3    2    2     1                                        __________________________________________________________________________

                                      TABLE 50                                     __________________________________________________________________________     Virus: Herpes Virus                                                            Dose Schedule: No pre-infection; +1, +49, +96, +120 post-infection.            Route of Administration: Oral                                                  Host: Mouse                                                                                  Total Dose Administered to the                                                 Animal in Micrograms                                             Compound: Semicarbazide                                                                      .005                                                                               .0005                                                                               .00005                                                                              .000005                                                                              Control                                      __________________________________________________________________________     Survivors     2   0    5    1     0                                            No. animals surviving                                                          when 100% of controls                                                          are dead      2   0    5    1     0                                            No. animals surviving                                                          after 9 days  2   1    5    1     11/2                                         __________________________________________________________________________

EXAMPLE 15

The following example illustrates the effect of prolonged pretreatment on the activity of the compounds useful in the practice of this invention against viruses. The results are shown in Tables 2, 3, 5, 51 and 52.

Several experiments were undertaken to demonstrate whether pretreatment for as much as six days influenced the antiviral effect of the drugs. Table 51 shows the influence of this on an Ann Arbor Influenza infection. It is evident that of the three drugs studied, all were effective with this prolonged administration prior to infection. This indicates that a triggering mechanism similar to Interferon induction is not at play in this phenomenon and it is believed indicates that the compounds of this invention are protective against viral infections on prolonged administration. Tables 3 and 39 illustrate the effect of at least two preinfection immunizations about 48 hours apart, and continuing at about 48 hour intervals for at least two post infection doses, the infection being 24 hours after the preinfection dose. A pronounced and significant effect is demonstrable on five of the hydrazine derivatives. Table 3 illustrates a schedule where the doses were given -96 and -48 hours preinfection, and the animals infected and dosed at about the same time followed by two more 48 hour drug administrations. It is evident that with semicarbazide there is very pronounced protection and quite significant protection with thiosemicarbazide.

                  TABLE 51                                                         ______________________________________                                         Virus: Influenza, Ann Arbor                                                    Dose Schedule: -140, -96, -48 pre-infection;                                   0, +48, +96 post-infection.                                                    Route of Administration: Oral.                                                 Host: Mouse                                                                                      Total Dose                                                                     Administered to the                                                            Animal in Micrograms.                                        Compound            .5    .05    .005 Control                                  ______________________________________                                         semicarba-                                                                             Survivors       1     1    1    0                                      zide                                                                                   No. animals surviving                                                          when 100% of controls                                                          are dead        1     1    1    0                                              No. animals surviving                                                          after 8 days    3     2    4     21/2                                  thiosemi-                                                                              Survivors       0     2    1    0                                      carbazide                                                                              No. animals surviving                                                          when 100% of controls                                                          are dead        2     3    1    0                                              No. animals surviving                                                          after 8 days    7     5    2     21/3                                  Isoniazid                                                                              Survivors       2     2    2    0                                              No. animals surviving                                                          when 100% of controls                                                          are dead        2     2    2    0                                              No. animals surviving                                                          after 8 days    6     5    5     21/2                                  ______________________________________                                    

                                      TABLE 52                                     __________________________________________________________________________     Virus: Herpes-Virus                                                            Dose Schedule: -50, -25 pre-infection;                                         +17, +65, +114 post-infection                                                  Route of Administration: Oral                                                  Host: Mouse                                                                                      Total Dose Administered to the                                                 Animal in Micrograms                                         Compound          5 .5                                                                               .05 .005                                                                               .0005                                                                               Control                                     __________________________________________________________________________     Hydrazine                                                                            Survivors   2 1 0   4   3    0                                           Sulfate                                                                              No. animals surviving                                                          when 100% of controls                                                          are dead    2 2 1   4   3    0                                                 No. animals surviving                                                          after 9 days                                                                               3 3 1   4   3    1/2                                         __________________________________________________________________________

The activity of 2-butanone thiosemicarbazone is shown in Tables 4, 10, 31, 33-35, 37, 39, 42 and 44. The tables illustrate the activity of the compound against Influenza, Vaccinia, Columbia SK polio and Herpes virus infections. It is one of the most active compounds that has been studied to date. It appears to be the most active of the compounds tested on Vaccinia in the mouse tail.

Thiosemicarbazide has been found to be active against Influenza PR 8, Vaccinia in the mouse tail, Mengo virus, Herpes virus in mice and eggs, Influenza virus, and Vaccinia virus in rabbits as shown in Tables 1-4, 10, 43, 44, 46, 47 and 51. The variability of some experiments from test to test is illustrated. It appears not to be as effective against many or most of these viruses as some of the other compounds of this invention. It is also active on Neurovaccinia virus in mice.

Semicarbazide hydrochloride has been shown to be effective against Influenza PR 8 virus, Vaccinia virus in the mouse tail, Herpes virus in eggs, Herpes virus in mice, Neurovaccinia, and Influenza Ann Arbor virus as shown in Tables 1-3, 6, 10, 11, 17, 32, 33, 39, 44, 45, and 48-51. It is quite active on Herpes virus, but may be less active on Influenza virus, Ann Arbor, and has even less activity on Influenza PR 8.

Hydrazine hydrate has been shown to be active on Influenza PR 8, Vaccinia in the mouse tail, Herpes in eggs, Herpes in mice, and Influenza Ann Arbor as shown in Tables 1, 8, 10, 12, 13, 15, 32, 33, 38, 44 and 52.

Isoniazid has been tested and found to be active against Influenza PR 8, Influenza Ann Arbor, Influenza B Mass., and Herpes virus as shown in Tables 4, 7, 9, 16, 17, 36, 39 and 51. The activity of this compound appears to be spread over a wide dose range and of reasonable degree of activity. The maximum protective effect that has been found is that 30% of the treated animals survived. In several instances as may be seen from the tables, animals show a prolongation of life well beyond the controls, indicating significant intrinsic activity.

Methisazone has been tested against Herpes virus, Influenza Ann Arbor and Influenza B Maryland, and found to have activity as shown in Tables 5, 7, 9, 15 and 41.

Hydralazine has been tested and found effective against Herpes virus as shown in Tables 5, 7 and 9.

Aminoguanidine bicarbonate has been tested against Influenza virus, Ann Arbor and B Mass., and found to have very pronounced protective effects when administered either orally or subcutaneously as is shown in Tables 14 and 40.

The following compounds have been tested and found effective in oral administration against Influenza Ann Arbor virus as shown in the tables opposite the compound:

    ______________________________________                                         Table      Compound                                                            ______________________________________                                         18    [(2,6-Dichlorobenzylidine)amino]guanidine acetate                        19, 20                                                                               3-Pentanone, thiosemicarbazone                                           21, 22                                                                               2-Pentanone, thiosemicarbazone                                           23    Acetone, thiosemicarbazone                                               24    1-(sec-Butylideneamino)guanidine, nitrate                                25    Acetoacetic acid, ethyl ester, thiosemicarbazone                         26    1,2-Dimethylhydrazine, dihydrochloride                                   27    1,1-Dimethylhydrazine                                                    28    Methylhydrazine                                                          29    2-Indanone, thiosemicarbazone                                            30    Cyclopentanone, 3-thio-4-o-tolylsemicarbazone                            ______________________________________                                    

The results of tests on other compounds found active are shown in Tables 53-65.

                                      TABLE 53                                     __________________________________________________________________________     VIRUS: Influenza, Ann Arbor                                                    Dose Schedule: -24, +24, +72                                                   Route of Administration: Oral                                                  Host: Mouse                                                                                Total Dose Administered to the Animal                                          3 300 30 3 300 30 3 300 30                                         Thiourea    mg                                                                               μg                                                                              μg                                                                             μg                                                                            ng  ng ng                                                                               pg  pg Control                                 __________________________________________________________________________     Survivors   0 1   0  0 0   0  1 0   0  0                                       No. animals surviving                                                          when 100% of controls                                                                      2 4   1  2 2   0  3 2   0  0                                       are dead                                                                       No. animals surviving                                                          after 7 days                                                                               5 6   3  7 2   4  3 4   2  4                                       __________________________________________________________________________

                                      TABLE 54                                     __________________________________________________________________________     VIRUS: Influenza, Ann Arbor                                                    Dose Schedule: -24; +24, +72                                                   Route of Administration: Oral                                                  Host: Mouse                                                                                Total Dose Administered to the Animal                                          3 300 30 3 300 30 3 300 30                                         Methylhydrazine                                                                            mg                                                                               μg                                                                              μg                                                                             μg                                                                            ng  ng ng                                                                               pg  pg Control                                 __________________________________________________________________________     Survivors   * 0   1  0 0   1  1 0   1  0                                       No. animals surviving                                                          when 100% of controls                                                          are dead    * 0   2  0 0   1  2 1   2  0                                       No. animals surviving                                                          after 6 days                                                                               * 1   3  3 1   4  3 3   2  21/2                                    __________________________________________________________________________      * Toxic?                                                                 

                                      TABLE 55                                     __________________________________________________________________________     VIRUS: Influenza, Ann Arbor                                                    Dose Schedule: -24; +3, +48, +72                                               Route of Administration: Oral                                                  Host: Mouse                                                                                 Total Dose Administered to the Animal                                          4 400 40 4 400 40 4 400                                           Nialamide    mg                                                                               μg                                                                              μg                                                                             μg                                                                            ng  ng ng                                                                               pg  Control                                   __________________________________________________________________________     Survivors    1 2   5  0 0   0  1 1   0                                         No. animals surviving                                                          when 100% of controls                                                                       1 3   5  0 0   0  1 1   0                                         are dead                                                                       No. animals surviving                                                          after 9 days 2 3   6  2 0   1  2 1   1/2                                       __________________________________________________________________________

                                      TABLE 56                                     __________________________________________________________________________     VIRUS: Influenza, Ann Arbor                                                    Dose Schedule: -24, +24, +72                                                   Route of Administration: Oral                                                  Host: Mouse                                                                                  Total Dose Administered to the Animal                            2-Indanone, 4-allylthio-                                                                     3 300 30 3 300 30 3 300 30                                       semicarbazone mg                                                                               μg                                                                              μg                                                                             μg                                                                            ng  ng ng                                                                               pg  pg Control                               __________________________________________________________________________     Survivors     1 0   0  0 0   0  0 0   0  0                                     No. animals surviving                                                          when 100% of controls                                                                        2 1   3  1 3   2  2 4   1  0                                     are dead                                                                       No. animals surviving                                                          after 7 days  4 2   6  2 6   6  4 7   4  4                                     __________________________________________________________________________

                                      TABLE 57                                     __________________________________________________________________________     VIRUS Influenza, A.sub.2, Taiwan                                               Dose Schedule: Part 1: -48, +1, +48, +72; Part 2: +1, +48, +72                 Route of Administration: Oral                                                         Compound:     Total Dose Administered to the Animal                     __________________________________________________________________________             Cyclobutanone, thiosemi-                                                       carbazone    40μg                                                                            4μg                                                                            400ng                                                                               40ng                                                                               4ng                                                                               .4ng                                                                              Control                             __________________________________________________________________________     -48, +1,                                                                               Survivors    1   3  1    3   0  0  1                                   +48, +72                                                                               No. animals surviving                                                  Part 1  when 18/20 of controls                                                                      1   3  1    3   0  0  1                                           are dead (18/20)                                                               No. animals surviving                                                          after 8 days 2   4  3    6   0  1  3                                                        30μg                                                                            3μg                                                                            300ng                                                                               30ng                                                                               3ng                                       No pre; Survivors    2   2  3    2         1                                   +1, +48, +72                                                                   Part 2  No. animals surviving                                                          when 18/20 of controls                                                                      3   3  3    3         1                                           are dead                                                                       No. animals surviving                                                          after 8 days 4   4  4    5         3                                   __________________________________________________________________________

                                      TABLE 58                                     __________________________________________________________________________     VIRUS Influenza A.sub.2, Taiwan                                                Dose Schedule: -24; +24, +72                                                   Route of Administration: Oral                                                  Host: Mouse                                                                                     Total Dose Administered to the Animal                                          30μg                                                                            3μg                                                                            300ng                                                                               30ng                                                                               3ng                                                                               .3ng                                                                              Control                                 __________________________________________________________________________     *  Survivors     3   4  2    3   3  4  1/2                                        No. animals surviving                                                          when 19/20 of controls                                                                       4   5  2    4   3  4  1/2                                        are dead (19/20)                                                               No. animals surviving                                                          after 8 days  7   5  4    5   4  4   11/2                                   ** Survivors     1   5  2    2   2  2  1/2                                        No. animals surviving                                                          when 19/20 of controls                                                                       3   5  3    2   3  3  1/2                                        are dead (19/20)                                                               No. animals surviving                                                          after 8 days  3   6  5    3   4  5   11/2                                   ***                                                                               Survivors     2   3  1    4   1  3  1/2                                        No. animals surviving                                                          when 19/20 of controls                                                                       3   4  1    5   1  8  1/2                                        are dead                                                                       No. animals surviving                                                          after 8 days  3   6  2    5   6  9   11/2                                   __________________________________________________________________________      * Cyclopentanone, o-tolylthiosemicarbazone                                     ** 3,5-Diamino-6-phenyl-1,2,4-triazine                                         *** 5-(1-Adamantyl)-1H-tetrazole                                         

                                      TABLE 59                                     __________________________________________________________________________     VIRUS: Influenza A.sub.2, Taiwan                                               Dose Schedule: -24; +24, +72                                                   Route of Administration: Oral                                                  Host: Mouse                                                                                 Total Dose Administered to the Animal                             5-(1-Adamantyl)-1H-                                                            tetrazole    30μg                                                                            3μg                                                                            300ng                                                                               30ng                                                                               3ng                                                                               .3ng                                                                              Control                                     __________________________________________________________________________     Survivors    2   3  1    4   1  3  1/2                                         No. animals surviving                                                          when 19/20 of controls                                                                      3   4  1    5   1  8  1/2                                         are dead                                                                       No. animals surviving                                                          after 8 days 3   6  2    5   6  9   11/2                                       __________________________________________________________________________

                                      TABLE 60                                     __________________________________________________________________________     VIRUS: Influenza A.sub.2, Taiwan                                               Dose Schedule: -24; +24, +72                                                   Route of Administration: Oral                                                  Host: Mouse                                                                                  Total Dose Administered to the Animal                            3,5-Diamino-6-phenyl-1,                                                        2,4-triazine  30μg                                                                            3μg                                                                            300ng                                                                               30ng                                                                               3ng                                                                               .3ng                                                                              Control                                    __________________________________________________________________________     Survivors     1   5  2    2   2  2  1/2                                        No. animals surviving                                                          when 19/20 of controls                                                                       3   5  3    2   3  3  1/2                                        are dead                                                                       No. animals surviving                                                          after 8 days  3   6  5    3   4  5   11/2                                      __________________________________________________________________________

                                      TABLE 61                                     __________________________________________________________________________     VIRUS Influenza, B Mass.                                                       Dose Schedule: -45; +1, +48, +96, +144                                         Route of Administration: Oral                                                  Host: Mouse                                                                                    Total Dose Administered to the Animal                          * Cyclohexanone, thiosemicar-                                                  bazone; Cyanoacetic Acid                                                       oxide**         500ng                                                                               50ng                                                                               5ng                                                                               500pg                                                                               50pg                                                                               5pg                                                                               Control                                __________________________________________________________________________     *  Survivors    1    5   2  2    2   5  2                                         No. animals surviving                                                          when 16/20 of controls                                                                      1    7   2  2    3   5  2                                         are dead                                                                       No. animals surviving                                                          after 11 days                                                                               2    7   3  2    4   7  4                                      ** Survivors    4    3   1  5    4   3  2                                         No. animals surviving                                                          when 16/20 of controls                                                                      4    4   2  5    4   3  2                                         are dead                                                                       No. animals surviving                                                          after 11 days                                                                               5    4   2  8    4   3  4                                      __________________________________________________________________________

                                      TABLE 62                                     __________________________________________________________________________     VIRUS: Herpes Simplex                                                          Dose Schedule: -46, +1, +45, +96                                               Route of Administration: Oral                                                  Host: Mouse                                                                                 Total Dose Administered to the Animal                             __________________________________________________________________________     Adamantyl thiosemicarba-                                                       zide         400ng                                                                               40ng                                                                               4ng                                                                               400pg                                                                               40pg                                                                               4pg                                                                               Control                                   __________________________________________________________________________     Survivors    3    2   2  3    1   1  1                                         No. animals surviving                                                          when 18/20 of controls                                                                      3    2   2  3    1   1  1                                         are dead                                                                       No. animals surviving                                                          after 9 days 3    2   4  3    2   2  2                                         __________________________________________________________________________

Tables 63 and 64 are a summary of the activity of the compounds described herein. Activity at the survival level is indicated with an "S". Activity at the increased geometric mean survival time level is indicated with a "P" for prolongation. Activity in certain specialized tests is indicated by either an "A" where active, or "I" where inactive. An "N" indicates that the test was not performed.

Significance at the survival level was recorded only for those tests on compounds in which two or more animals survived at least three different dose levels or at least three animals survived at a single dose level in tests in which a minimal number of controls survived. Significant prolongation is recorded only where a large number of treated animals survived at the time that almost all of the controls animals were dead. In those instances where a given test has been repeated two or more times, the significance of the most active test is recorded in the chart.

The classes to which the compounds belong may be conveniently summarized as follows:

1 a. Thiosemicarbazone

b. Substituted thiosemicarbazone

c. Thiosemicarbazide

2. Semicarbazide

3. Hydrazine

4 a. Hydrazide

b. Substituted hydrazide

5 a. Aminoguanidine

b. Substituted aminoguanidine

6 a. Indazoles

b. Phthalazine

c. Triazine

7 b. Tetrazole

                                      TABLE 63                                     __________________________________________________________________________                    Influ-                  Vac-                                                                               Vac-                                                                               Neuro-                                                                             Colum-                                     enza                                                                               Influ-  Influ-      cinia                                                                              cinia                                                                              vac-                                                                               bia SK  Cox-                           Influ-                                                                             A.sub.1                                                                            enza                                                                               Influ-                                                                             enza B                                                                             Herpes                                                                             Herpes                                                                             in  in  cinia                                                                              Polio                                                                              Mengo                                                                              sackie                         enza A                                                                             Ann A.sub.2                                                                            enza B                                                                             Mary-                                                                              in  in  Mouse                                                                              Rab-                                                                               in  in  in  in                  COMPOUND   PR 8                                                                               Arbor                                                                              Taiwan                                                                             Mass.                                                                              land                                                                               Mice                                                                               Eggs                                                                               Tail                                                                               bits                                                                               Mice                                                                               Mice                                                                               Mice                                                                               Mice                __________________________________________________________________________     Isoniazid  P   S   I   S   P   P   N   N   N   N   N   N   N                   Nialamide  N   S   N   N   N   N   N   N   N   N   N   N   N                   Hydralazine                                                                               I   I   N   N   P   P   S   N   N   N   N   N   N                   Adamantyl  N   N   N   N   N   P   N   S   N   N   N   N   N                    thiosemicarbazide                                                             [(2,6-dichlorobenzyl-                                                                     N   P   N   P   N   N   S   N   N   N   N   N   N                    idene)amino]                                                                   guanidine                                                                     Thiosemicarbazide                                                                         S   P   N   S   S   S   S   S   S   P   P   P   N                   2-Butanone,                                                                               S   P   S   S   P   S   S   S   I   I   P   P   I                    thiosemicarbazone                                                             3-Pentanone,                                                                              N   P   N   P   N   P   S   N   N   N   N   P   N                    thiosemicarbazone                                                             2-Pentanone,                                                                              N   P   N   N   N   P   N   N   N   N   N   P   N                    thiosemicarbazone                                                             Acetone,   N   P   N   N   N   N   N   N   N   N   N   S   N                    thiosemicarbazone                                                             1-(sec-Butylidene-                                                                        N   P   N   N   N   N   N   N   N   N   N   N   N                    amino)quanidine,                                                               nitrate                                                                       Acetoacetic acid,                                                                         N   P   N   N   N   N   N   N   N   N   N   N   N                    ethyl ester,                                                                   thiosemicarbazone                                                             Hydrazine sulfate                                                                         S   S   N   S   P   S   S   S   N   I   N   N   N                   Semicarbazide,                                                                            S   S   N   P   P   S   S   S   N   P   N   N   N                    hydrochloride                                                                 Cyclohexanone,                                                                            N   N   N   S   N   N   N   N   N   N   N   N   N                    thiosemicarbazone                                                             Aminoguanidine,                                                                           N   S   N   S   N   N   S   N   N   N   N   N   N                    bicarbonate                                                                   Methisazone                                                                               P   P   N   N   P   S   I   N   N   N   N   N   N                   __________________________________________________________________________

                                      TABLE 64                                     __________________________________________________________________________                          Influenza                                                                             Influenza                                                                            Influenza                                                                            Influenza                                                                            Herpes                                                                              Herpes                                                                              Vaccinia                                    A.sub.1                                                                               A.sub.2                                                                              B     B     in   in   in                     COMPOUND             Ann Arbor                                                                             Taiwan                                                                               Mass. Maryland                                                                             Mice Eggs Mouse                  __________________________________________________________________________                                                             Tail                   sym-Dimethylhydrazine dihydrochloride                                                               P      N     N     N     N    N    N                      unsym-Dimethylhydrazine                                                                             P      N     N     N     N    N    N                      Methylhydrazine      P      N     N     N     N    N    N                      2-Indanone, thiosemicarbazone                                                                       P      N     N     N     N    N    N                      2-Indanone, 4-allylthiosemicarbazone                                                                P      P     N     P     N    N    N                      Cyclopentanone, o-tolylthiosemicarbazone                                                            P      S     N     N     N    N    N                      3,5-Diamino-6-phenyl-1,2,4-triazine                                                                 N      S     S     N     N    S    N                      Cyclobutanone, thiosemicarbazone                                                                    N      S     P     N     N    S    N                      Cyanoacetic Acid Hydrazide                                                                          N      N     P     N     N    N    N                      5-(1-Adamantyl)-1H-tetrazole                                                                        P      S     N     N     S    N    S                      __________________________________________________________________________

EXAMPLE 16

A portion of a commercially available sample of amantadine was recrystallized from isopropanol. The activity of the material against Influenza B Mass. was tested for the sample as obtained, the recrystallized portion, and the mother liquor obtained from recrystallizing the portion. The results are shown below in Table 65. All three were found to be active in the chemoprophylaxis of Influenza B Massachusetts in the dose ranges used. Amantadine has been reported in the literature to be ineffective against Influenza B Massachusetts in larger doses and at different dose schedules. Effective chemoprophylaxis was obtained at doses ranging from 3 nanograms to 9 milligrams per mouse weighing 16 to 20 grams. This is equivalent to a dose of about 150 nanograms to 450 milligrams per kilogram of host body weight. Effective results were obtained at dose schedules of 24 and 48 hours.

                                      TABLE 65                                     __________________________________________________________________________     VIRUS: Influenza B Massachusetts                                               Dose Schedules: -72, -24, +24, +72, +123, +144                                 Route of Administration: Oral                                                  Host: Mouse                                                                                        Total Dose Administered to the Animal                                           6                                                                               600 60 6 600 60                                                              mg                                                                               μg                                                                              μg                                                                             μg                                                                            ng  ng Control                                  __________________________________________________________________________     Commercial                                                                            Survivors    2 5   2  5 3   0  0                                        amantadine                                                                            No. animals surviving                                                          when 100% of controls                                                                       2 5   2  5 3   0  0                                               are dead                                                                       No. animals surviving                                                          after 11 days                                                                               4 5   3  7 3   3   11/2                                           Survivors    4 2   2  5 3   2  0                                        Recrystal-                                                                            No. animals surviving                                                   lized  when 100% of controls                                                                       4 2   2  5 3   2  0                                        amantadine                                                                            are dead                                                                       No. animals surviving                                                          after 11 days                                                                               6 3   5  5 3   4   11/2                                    Mother Survivors    3 3   4  4 6   1  0                                        liquor from                                                                           No. animals surviving                                                   recrystal-                                                                            when 100% of controls                                                                       3 3   4  4 6   1  0                                        lizing are dead                                                                amantadine                                                                            No. animals surviving                                                          after 11 days                                                                               4 4   5  7 7   1   11/2                                    __________________________________________________________________________

When the compounds of this invention are employed as described above, they may be administered alone or in combination with pharmacologically acceptable carriers, the proportion of which is determined by the solubility and chemical nature of the compound, chosen route of administration and standard pharmacological practice. For example, they may be administered orally in the form of tablets or capsules containing such excipients as starch, milk, sugar, certain types of clay and so forth. They may be administered sublingually in the form of troches or lozenges in which the active ingredient is mixed with sugar and corn syrups; and then dehydrated sufficiently to make it suitable for pressing into a solid form. They may be administered orally in the form of solutions or they may be injected parenterally, that is intramuscularly, intravenously or subcutaneously. For parenteral administration they may be used in the form of a sterile solution containing other solutes, for example, enough saline or glucose to make the solution isotonic.

The dosage of the present pharmacological agents will vary with the form of administration and the particular compound chosen. Furthermore, it will vary with the particular subject under treatment. In general, the compounds of this invention are most desirably administered at a concentration level that will generally afford effective results without causing any harmful or deleterious side effects. For example, the unit dosage quantities of a dosage form for administration to a 60 kilogram host may range from 250 picograms to 15 milligrams.

A solid oral dose form may be prepared as follows:

A predetermined weight of a comminuted compound of this invention is intimately mixed with predetermined amounts of extenders, lubricants, flavoring and the like. The mixture is then subjected to sufficient pressure to form a medicinal tablet for oral medication.

A general tablet formula is:

    ______________________________________                                         Compound of the present invention                                                                    15 ng to 15 mg                                           Extenders, lubricants, flavoring                                               and the like          50 to 800 mg                                             A particular tablet formula is:                                                Hydrazine hydrochloride                                                                              12 mg                                                    Propanol              40 mg                                                    Mannitol N.F.         150 mg                                                   Starch U.S.P.         19 mg                                                    Sucrose               2.7 mg                                                   Magnesium stearate U.S.P.                                                                            4.0 mg                                                   Granulated milk sugar 220 mg                                                   ______________________________________                                    

To prepare an injectable dose form a predetermined weight of a comminuted compound of the present invention is dissolved in distilled water along with pharmaceutically acceptable compounds to render the solution isotonic. The solution is then filled into a disposable cartridge for use with a syringe for use as dosage form for parenteral administration.

The terms and expressions which have been employed are used as terms of description and not of limitation, and there is no intention in the use of such terms and expressions of excluding any equivalents of the features shown and described or portions thereof, but it is recognized that various modifications are possible within the scope of the invention claimed. For instance, the pharmaceutically acceptable acid addition salts of the compounds may be substituted one for the other or for the compound itself.

Without wishing to be bound by a theory of operation it is postulated that the activity of compounds may be due to the alpha effect. The alpha effect is a phenomenon that has been observed in which two electronegative atoms that are adjacent may react with a carboxylic acid group much more strongly than would be predicted from the actual basicity of the compounds. It appears that two electronegative atoms adjacent are essential for the augmentation of reactivity, but not all compounds with two electronegative atoms show equally pronounced alpha effects. It has been found that some compounds having a nitrogen-oxygen bond are active in the practice of this invention, for example, N-hydroxyphthalamide and phenylglyoxaloxime. 

What is claimed is:
 1. A method of controlling a virus infection in a host suffering from a virus infection in which the virus is a member of the class consisting of Herpes simplex, Vaccinia, Influenza A (PR8), Influenza A₁ (Ann Arbor), Influenza A₂ (Taiwan), Influenza B (Mass.), Influenza B (Maryland), Mengo, Columbia SK polio, and Neurovaccinio comprising orally administering to the animal host from 250 picograms to 250 micrograms per kilogram of host body weight of a compound is selected from the class consisting of:A. 2-butanone, thiosemicarbazone B. 3-pentanone, thiosemicarbazone C. 2-pentanone, thiosemicarbazone D. acetone, thiosemicarbazone E. acetoacetic acid, ethylester, thiosemicarbazone F. cyclohexanone, thiosemicarbazone G. cyclobutanone, thiosemicarbazone H. 2-indanone, thiosemicarbazone I. 2-indanone, 4-allythiosemicarbazone J. cyclopentanone, o-tolylthiosemicarbazone K. adamantyl thiosemicarbazide L. thiosemicarbazide M. methisazone N. semicarbazideand the pharmaceutically acceptable acid addition salts thereof.
 2. A method as defined in claim 1 in which the compound is administered orally.
 3. A method as defined in claim 1 in which the compound is administered in the form of a tablet, capsule or solution.
 4. A method as defined in claim 1 in which the compound is administered at 48 hour intervals.
 5. A method as defined in claim 1 in which the compound is administered either before or after infection or both before and after infection.
 6. A method of controlling a virus infection in a host suffering from a virus infection in which the virus is selected from the group consisting of Herpes simplex, Vaccinia, Influenza A (PR8), Influenza A₁ (Ann Arbor), Influenza A₂ (Taiwan), Influenza B (Mass.), Influenza B (Maryland), Mengo, Columbia SK polio, and Neurovaccinio comprising orally administering to the animal host from 250 picograms to 250 micrograms per kilogram of host body weight of a compound selected from the group consisting of:A. 2-butanone, thiosemicarbazone B. 3-pentanone, thiosemicarbazone C. 2-pentanone, thiosemicarbazone D. acetone, thiosemicarbazone E. cyclohexanone, thiosemicarbazone F. cyclobutanone, thiosemicarbazone G. cyclopentanone, o-tolylthiosemicarbazoneand the pharmaceutically acceptable acid addition salts thereof.
 7. A method as defined in claim 6 in which the compound is administered orally.
 8. A method as defined in claim 6 in which the compound is administered in the form of a tablet, capsule or solution.
 9. A method as defined in claim 6 in which the compound is administered at 48 hour intervals.
 10. A method as defined in claim 6 in which the compound is administered either before or after infection or both before and after infection. 